Practical Microscopy

Tobacco Hornworm (Manduca sexta) and the Parasite Wasp (Cotesia spp.)

2011-08-31T21:34:00.000-04:00

The picture on the left is the tobacco hornworm (Manduca sexta) that infested my tomato plant. The insect belong to Sphingidae family, commonly known as hawk moth. The tobacco hornworms can be distinguished from the closely related tomato hornworms by their seven diagonal stripes versus eight v-shaped marking on the tomato hornworms. The most striking feature of the hornworm is the thick pointing structure (or horn) located dorsally on the terminal abdominal segment. On the back of the larvae, there are clusters of parasite wasp cocoons which has be infested the larvae and emerge from the skeleton.

This post, I am getting some close-up view of the tobacco hornworm and the parasite wasps under a stereo microscope.

Close-up of the tobacco hornworm

Mandible of the larvae (slightly out-of-focus are the thoracic legs)	Ocelli
Thoracic legs	The tip of the prolegs on abdomen. Now, you know why it is so hard to remove the caterpillar from the tomato vine. They are full of “claws”.
Spiracles	Another view of the spiracle (with 4x objective rather than 2x)
The spiracles and the lesions caused by the parasite wasps
The terminal segment of the abdomen. The end is full of spikes. That’s how they stick to the vine when you are trying to pull them off the vine.	The horn - “signature” of the tobacco hornworm.

The parasite Wasp

Day3 (8/29/2011): The cocoons of the parasite wasp at the dorsal of the tobacco hornworm (this picture was taken about 48 hour after we collected the hornworm)	Cut open the cocoon, there was a larvae inside
Continue to peel open the cocoon. Here’s full view of the larvae.	Day 4 (8/30/2011): Just one day after I opened up the cocoon. Apparently there was a big change inside of the larvae. It’s already taking the shape of the wasp and with legs and pigmented eyes developed.
Day 5 (8/31/2011): Start to show darker pigmentation	Day 6 (9/1/2011): Even Darker pigmentation. Still no movement
Day7 (9/2/2011): The appendages and antennas are starting to extend out and show some movement. Occasionally, it would tweet its legs or antenna. Wings are more visible now.	The wasp starting out with cutting a ring close to the top of the cocoon.
It did not cut all the way through. It started to push when it the cut was about 90 percent of the circumference.	Continue to push. First the antenna then the two front legs.
	Finally, completely came out of the cocoon.

The wasp that was removed from the cocoon did not survive. Its wing did not extended out fully. The picture on the left was another wasp that came out of cocoon on the same date. The pictures were combined using Microsoft image composite Editor since the antenna are very long and extended out of the field of view.

Video recording of the parasite wasp come out of the cocoon

Sand from Thermal City Gold Mine

2011-08-14T14:50:00.001-04:00

Returning from Thermal City Gold mine yesterday and spending most of the day learning how to get rich from panning gold. The science behind of gold panning is based on the gold density. After stirring up the gold containing sand, the heavier gold will sink to the bottom while other materials will stay on the top. The process involved in continuous removal of lighter sand on the top and eventually the heavier gold will become more concentrated. I heard from staff there are plenty of microscopic gold in the sediment. I brought home a bag of sand from the last stage of panning which contains plenty of black sands (Magnetite) and hopefully some microscopic gold in there.

Figure 1 The remaining sand of the last step of gold panning process contains very high percentage of black sand. Many of the black sands are in fact Magnetite, an ferromagnetic mineral with chemical formula of Fe₃O₄. Some green colored crystals are olivine, an magnesium iron silicate with the formula of (Mg,Fe)₂SiO₄. I suspect the the pink colored crystals are rubies which are also found in the area. Of course, the majority of the colorless crystals are quartz which is the most common mineral in the sand.

Figure 2 WE FOUND GOLD!! These are the two pieces I found in my last pan. It would have been such a big disappointment without finding any gold during the field trip. The length of the gold is about 1mm. That’s the size that most of us found. Some of the folds do find some flakes about 3-4 mm.

Figure 3 A piece a mica in the sand. Lots of people mistake these as gold due to their metallic reflection. They can be easily distinguished from gold because they change the reflection when looked from different angle.

Minerals from Thermal City Gold Mine

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Contrast enhancement for plant cell viewing

2011-08-10T22:55:00.001-04:00

It’s difficult to see cells under a regular brightfield microscope when they don’t have pigment or stained with color. The reason is that the light source of a brightfield microscope was placed directly underneath the specimen. The light penetrate the specimen to illuminate the specimen and finally reach your retina. There is very little deflection of the light to create the contrast. Some simple filters can be added to the optical train to create the contrast.

Figure 1. Onion epidermis cell under regular brightfield microscope.

Figure 2. adding a darkfield filter to the light path, the cell wall can be easier to see.

Figure 3. Based on the darkfield technique, The Rheinberg illumination, a form a optical staining, can stain the specimen without chemical stain. The method used a color filter consists of two or more colors to allow the light with different color come from different direction which create the structure to be “Stained” with different color. The above image was viewed under a Rheinberg filter with green center and red peripheral.

Figure 4. Of course, it is inevitable to use chemical staining if the structure of interest has very different chemical composition but very little in deflecting light. The above picture is an onion epidermis cell with the nucleus in the center. The specimen was stained with Methylene blue. The nucleus was darker because methylene blue has stronger binding to nucleic acid than cytoplasm.

The steps for making the filters was described earlier at Laboratory and Home Science Resources.

Ibuprofen Crystal Growing Habit in Different Solvents

2011-08-06T00:05:00.004-04:00

The microcrystalline test is a procedure used by the scientists to identify the substances with birefringent property. The scientist adds a drop of the suspected substance to a chemical on a slide. The mixture will begin to form crystals. Each type of drug has an individual crystal pattern when seen under a polarized light microscope (PLM).
I was cleaning up my medicine cabinet and found a bottle of expired ibuprofen. Instead of throwing it away, I decided to try it out under PLM. The medicine has brown coating, it was easily removed by rinse off with water. The interior is crystal white. I dissolved one pill in water and another one in 95% Ethanol. The solution was left overnight get it as close to as saturation as possible.

Ibuprofen formed in water

Ibuprofen formed in ethanol

The ibuprofen crystals formed in water showed more compact form than the crystals formed in ethanol. The crystals formed in ethanol have feather like shape and less compact. Here is my explanation: Compared to water, ethanol has less surface tension so they spread out quickly so it has larger surface area. In addition to having larger surface area, ethanol also has lower boiling point so it evaporate quickly. Ibuprofen has less chance to form compact and organized crystals.

Making whole insect slide – an easy way

2011-07-28T00:07:00.001-04:00

In the previous post, I presented a modified method of microscope slide making originally described by Schauff. The method involved four steps: maceration, cleaning, dehydration and mounting. The process removes the non-transparent internal organs and preserves the chitin exoskeleton. It allows the clear viewing the minute details of insects at high magnification using a compound microscope. It does has draw backs, including the use of caustic reagents and the potential of damaging the specimen using picks for cleaning. Sometime, you may not need to observe them in high magnification and wanted to preserve their natural shape. I came across a website (forgot to bookmark it. I lose the link and can’t seem to find it back.) which directly mounted the insects stored in alcohol. The protocol used Xylene and Canada balsam. I decided again using the less toxic alcohol and nail polish top coat.

The first stop is to build a shallow well to create space so that the insects won’t be crushed by the slide and maintained the natural shape. I found the electronic plastic package material will serve me well for this purpose. The thickness is about 0.5mm. It’s not too deep that I had to fill in lots of mountant but not too shallow to allow the cover slip to crush the insect. It’s hard enough to maintain the shape but soft enough to cut with a pair of scissor.

The first step was to cut a piece of plastic to the size slightly smaller than the slide but larger than the cover slip. The next is to make some holes with hole puncher – can be purchased from regular office supply store. Apply some finger nail top coat on one side of the plastic. Glue it to the slide and wait until it dried. Pick up the insects from the preservation alcohol then transfers them to the well with a pair of tweezers. Use the pick to adjust the body orientation and appendages to show their natural position. Put a few drops of finger nail polish top coat in each well until it slightly over the top of the plastic. Care should be taken to ensure that no bubble is introduced into the mountant. Any bubble introduced into the mountant will be enlarged after the mountant dried out.

An aphid nymph was mounted upside down to show the under side of the insect.

An aphid nymph top view

Wing adult aphid

This post, I presented an easy method for mounting insect onto microscope slide. The method is not appropriate for view the insect at high magnification for certain non-transparent body parts but it is appropriate for the viewing at low magnification with a stereo microscope using the top light.

Insect Slide Preparation for Microscope Examination

2011-07-24T00:04:00.000-04:00

My first attempt of insect slide making was not a successfully one but I think the experience worth to share, especially for those DIY hobbyists. I was very excited to find an insect slide making reference published by Schauff from USDA. The Schauff's protocol can be generalized by the following steps:

1) Maceration (cleaning): Using caustic reagents, such as sodium hydroxy, potassium hydroxy, lactophenol or lactic acid , to remove external secretions, foreign matters, some organs, and fat bodies. The purpose is to remove those parts without damaging the chitinous parts. Heating the specimen in the maceration reagent can accelerate the process. 2) Washing: Removing the caustic agents with tap water in a small dish for at least a few minutes. 3) Staining, Bleaching and Dehydration: Staining and bleaching are optional steps to improve the viewing ability of the insect. Stain it, if too light. Bleach it, if too dark. Any residual water in the specimen needs to be removed before mounting - it is not mixable with water. 4) Mounting: Mounting for microscopic examination can be temporary or permanent. temporary slide can be made with acetic acid on a cavity slide. The permanent mount can be done with Canada Balsam, Euparal or Hoyer’s medium and polyvinyl alcohol (PVA).

In this trials, aphids an ants (that protects the aphids) found on my loquat tree were chosen to make the microscope slides because they are readily available from backyard. My protocol adopted Schauff's protocol but slightly modified and using the generally available household chemical. :

1) Maceration: This step is done with 10% sodium hydroxy solution. To make the solution, I added 1 gram of Roebic heavy duty crystal drain opener (Picture on the Left) in 10 mL tap water. The Roebic Heavy duty crystal drain opener contains 100 percent sodium hydroxy, according to the manufacturer's MSDS. There are other types of drain opener in the home improvement store, but this is the only one contains one hundred percent sodium hydroxy. Candle warmer container is used for the maceration. The sodium hydroxy will gradually turned yellow when it started to digest the insect’s internal organs (Right). I varied the length of maceration from 24 to 72 hours – the longer I left the insects in sodium hydroxy, the more transparent they are.

2) Cleaning: The insects were picked up by a pair of tweezers and transferred to tap water. I gently pipetted the contents to allow sodium hydroxy to be diluted faster. I repeated it for the second time by siphoning up the supernatant. The supernatants were discarded and the insects were left in the in the container. Another 10 to 15 mL tap water was added and repeat the some process. The insects are now partially transparent but still has some contents in the abdomen and thorax.

3) Dehydration and more cleaning: This step is done by Crown Denatured Alcohol Next which contains about 95 percent ethanol (The rest of the ingredient is isopropanol) – Crown has another denatured alcohol contains methanol. I like the one labeled as “Next” and “95 Percent nature content” because ethanol is less toxic. Again, I siphoned water from the cleaning solution and left the insects in the candle holder then added 10 to 15mL denatured alcohol. The container of alcohol wasn’t helping me to pour the alcohol out. I used the funnel to help but it still got messy. The insects were left in alcohol for about 30 minutes then I started the cleaning. This time was the internal organs of the insects. There are still plenty of contents resided in the exoskeleton of the insects and surrounded the carcasses – I believed that they were denatured proteins an nucleic acids which were precipitated out then I added alcohol. I cleaned them up with a pair of picks. I siphoned the cleaned insects up and transferred it to a different container containing the denatured alcohol. I did more cleaning after the transfer to remove any protein and nucleic acid residues (right).

4) Mounting: The insects were siphoned up and transferred to a microscope slide. I tried to picked up as little alcohol as possible so that the alcohol won’t spill over or messed up the insects already on the slide (Several insects were mounted on the same slide and in different position). The position and the posture of the insects were manipulated with picks to optimized the viewing – extending legs, minimized the wrinkles, changed orientations, making the posture natural etc. A few drops of clear fingernail polish top code were added to the slide to cover the insects. A cover slip was placed on the top to finish the mounting. I waited overnight to allow the finger nail polish to harden before viewing on the microscope.

The following are the pictures from the insect slides made from this experiment: Because this was my first attempt to make insect slides, it’s an trial and error process, not all pictures are using the same condition. In the future post, I will summarize the process and post the optimized condition. For example: Some slides were made with 24 hours of maceration, it tends to show more internal organs and less transparent. The aphid body tends to show better skeleton when they were processed with longer maceration. They also varied with degree of cleaning. The aphid bodies contain lots of fluids and rich in protein. They tend to become less transparent when immerged in alcohol,. The body contents needs to be squeezed out with a pair of picks. Some specimens were not cleaned too well which leaved body parts in the specimen while others were cleaned very well but the extensive cleaning caused the body to be broken apart.

Aphid Slides

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The ants seem to be easier to process then the aphids because of harder exoskeleton. They don’t disintegrated like the aphid’s body do. They don’t have lots of body fluids. This makes the cleaning much easier then the aphids.

Ant Slides

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Some suggestions about insect slide making:

The protocols can varied among different insects. Some insects have harder exoskeleton and can resist harsher processing condition while other were softer which required gentler processing condition. For example, some insect can allow to be boiled in NaOH solution while others can only left in room temperature overnight. Some required extra physical cleaning while others can only resist chemical cleaning. The body size can also determine how much processing time. Some insects are so big that you need to punch a hole between segments to allow reagent to penetrate.
To accelerate the maceration process, some gentle heating might be required (Note: if you are heating the NaOH, make sure that you used a container that can allow direct heating. The candle holders used in this experiment are not. I actually blow up a candle holder by putting it on the top of the 900 W outdoor food warmer! An electronic candle warmer might be used.)
If you need to squeeze out the body content, do it during cleaning step rather than dehydration step. This will minimized the amount of body fluid denatured in the alcohol – less cleaning.
Use siphon suck up the insect along with some liquid that the insects are in. This might work better than tweezers or picks, especially after you squeeze the body content out. The body is very fragile.
Take your time. Be patient and gentle.
Use Canada balsam if available – I think this is give or take. The advantage of using Canada balsam is the color less and less shrinking than finger nail polish top coat but it required Xylene for dehydration. Xylene is very toxic. While the finger nail polish shrink a lot but you can put insect in ethanol directly in finger nail polish top coat without any problem.
Use concaved slides or build some wall on the slide to allow more depth if you are doing the whole insect mount.

Reagents, contains and tools can be found in your home. If not, they can be easily found in the home improvement stores (such as Lowes or Homedepot), dollar stores or grocery stores. I’ve found many of these can be found at Amazon.com. (The only thing that I could not find there is the Crown denatured alcohol (which contains 90-95% Ethanol and 5-10% isopropanol. Amazon only has reagent grade ethyl alcohol.).

Granites from Vulcan Material Company Kennesaw Granite Quarry

2011-07-17T22:39:00.021-04:00

Vulcan material company's Kennesaw quarry supplies granites or granite related materials for industries and local construction. To make granite for available for it's application, the size needs to be reduced by blasting, crushing with a metal weight, crushing with jaw crusher then going through various sorters to separate different sizes. The query is currently mining below 600 feet deep but the location we visited is at the upper level. The appearances of the granites collected from the location varied greatly according to their compositions: quartz, mica, feldspar and amphibole.

Vulcan Kennesaw quary granite

This piece of rock is very soft and easily crumbled in my hand. Some flaky
mineral were shining under the sun light. My daughter called it fool's gold.
Under a stereo microscope, they are flaky, like micas)

Crystals of quartz (white) and micas (black) Granite under
stereo microscope.

This piece contains feldspar (pink)

a red strip on a piece of granite.

Stilbites were find in the cavity of a piece of granite It seems to be a nice piece for making micromount.

Aphids infestation of Asian Persimmon and Loquat

2011-07-16T00:19:00.006-04:00

I found lots of the tender leaves of my Asian persimmon and loquat tree all curl up. The ants are climbing up the tree for something. After peeling open the the Persimmon leaves, there are hundreds of tiny green and yellow dots on the leaves and ants are crawling around it. It seems to be particular bad this year due to the unusual warm spring. After treating my Persimmon trees with fruits sprays, it got better for couple weeks then they come back again. After surveying other trees in my yard, I found that my loquat trees got the Aphids too. They aggregated on the back side of the leaves of the new shoots.

The tender leaves of my persimmon tree curled up.

Many aphids hid at the back side of the tender leaves of

loquat tree

I think I've found the reason why I can never stop the infestation of the aphids of my Asian persimmon. The loquat tree appears to be the alternative host for those aphids. As I killed the aphids on the persimmon trees, the aphids are continueing to spread from the loquats. I decidd to pick a few tender leaves from the loquat tree to look at under my microscope. The aphids are very lazy insects. As I picked the leaves, the ants are all scared and running around. The green dots (aphids) stayed calm and still enjoying the juice from succulent tender leaves. I looked at those tender leaves under my stereo microscopes at 20X or 40X. The tiny green dots now appears to be aphids

The aphids like to aggregates on the veins of the tender leaves to suck

the juice.

Found a few winged adults in the colony.

The pictures of aphids were taken with Tucsen 3.0 MP CMOS microscope camera from Ample Scientific SM-Plus stereo microscope. The eyepiece needs to be removed and inserted the adaptor with the 30mm adaptor ring for photo taking.

Staurolite Collection Field Trip to Marble, North Carolina

2011-07-14T22:39:00.004-04:00

Staurolites crystals can be collected from the river next to the

pacesetter camp

The name Staurolite is derived from the Greek, stauros for cross and lithos for stone in reference to the common twinning. A special property of staurolite is that it often occurs twinned in a characteristic cross-shape. Staurolite crystals has a Mohs hardness of 7 to 7.5 and a rather complex chemical formula: (Fe,Mg,Zn)₂Al₉(Si,Al)₄O₂₀(OH)₄With Iron, magnesium and zinc occur in variable ratios. Macroscopically visible staurolite crystals are of prismatic shape. They are often larger than the surrounding minerals and are then called porphyroblasts.

The middle of the river has plenty of

larger rocks. They need to be

removed be

An official field trip of Gem and Mineral Society of Franklin, NC brought us to the Pacesetter camp in Marble, North Carolina to collect Staurolite. Staurolite can be found in the river next to the camp. The water was mostly shallow except one area where the water was become stagnant. There are plenty of big rocks on middle of the river bed. They need to be removed and get to the pebble and sandy layer. Scoop up a shavelful of the gravel or sand and place them in the screenbo. Allow smaller sand and pebbles to go through the screen and carried away by the river. The Staurolite crystals are larger and retained on the screenbox (Instruction for making screenbox).

The 1/2 inch mesh screenbox

The staurolite crystals collected from the middle of the river are more rounded in shape because of the tumbling effect from the river while the staurolite crystals collected from the size of the river tends to be more angled. Belows are the Staurolites collected from the field trip.

The twinned Staurolite crystals are the most saught after form. I collecte each one of them in the field trip. They are collected from the middle of the river so they are very short and rounded.

Twinned staurolite crystal crossed in ninety degree angle.

Twinned staurolite crystal crossed in sixty degree angle.

Most Staurolite Crystals are not twined

Staurolites under stereo microscope. The color of Staurolite

can be any where from brownish to black.

In thin sections staurolite is commonly twinned and shows lower first order birefringence similar to quartz, with the twinning displaying optical continuity. It can be identified in metamorphic rocks by its swiss cheese appearance (with poikilitic quartz) and often mantled porphyroblastic character. This will be my next project.

PS. After couple days since my first collection of pond water. Most pond lives are mostly disappears. They were either died or go into hibernation. I am thinking it either lack of oxygen or energy. Summer is the season for observing pond lives. I will postpone the making of thin section of staurolites until the summer is ended.

Creatures living in a dirty pond

2011-07-11T22:35:00.037-04:00

Dirty pond? It looks dirty but that's from human's perspective but it might be the most healthy environment for the organisms living there. During the summer, the pond is full of living creatures that feeds on microorganisms whose population is exploding owing to the warm weather. Summer should be the season for the celebration of life. I found the pond of the nearby Brisco park is full of green algae. The density and varieties of the creatures living in the water is amazing.

I took couple drops of water from the top of the collection tube and drop them in a concave slide. The water is very concentrated with colonies of Volvox - a very popular green algae as model organism for research. Rotifers are also abundent in the collection.

A colony of Volvox. Therea re hundreds of cellls per colony. I found most Volvox images on the Internet are spherical but most colonies I observed are somewhat irregular. I suspected the the shape of the Volvox colony is distroyed by the predatory rotifer, Euchlanis.

a Rotifer (Euchlanis sp.) is swimming in the matrix of Volvox colony.

A group of stentors are feeding. Some green algea colonies are apparently ingested by the stentors.

A flatworm is gliding through green algae matrix

a seed shrimp (Ostracod)

Water mite.

A Desmid (Microasterias sp.)

Cosmarium sp.

On the top is spirogyra and bottom is an unidentified diatom

Scenedesmus sp.

On the left is the Pediastrum, on the right is a Staurastrum.

Of course, on the top of those microorganisms and microscopic animals (such as rotifers, copepods and seed shrimps) in the food chain are those with bigger mouth. I found plenty of tadpoles in the pond. Fueled by the warm and sunny weather, the green algea populations are booming. On top of this is the faster nutrient break down and growth of the microsorganisms. The predatory protozoa and microscopic animals has plenty to feed on. All the energy is feeding toward to top of the food chain. I have no surprise to find that many tadpols in the pond.

How about those canadian geese? They've flown thousands of miles to have the feast!

Moth infested my Asian Pear

2011-07-09T23:49:00.001-04:00

Couple moth ago I encounter serious problem of insect infestation of my Asian pear. The secret is finally revealed. The insect infested my Asian pear tree is the codling moth. I catched several adult moths in my front yard.

More links about codling moth:
http://en.wikipedia.org/wiki/Codling_moth
http://crawford.tardigrade.net/bugs/BugofMonth33.html

The Beach Sand of the Gulf of Mexico under Polarized Light Microscope

2011-06-29T22:12:00.001-04:00

Siesta Beach is known as one of the most beautiful beaches in the world. At the "Great International White Sand Beach Challenge" held in 1987, it was recognized as having the "whitest and finest sand in the world." The sand is so reflective that it feels cool underfoot even on the hottest days. What's the reason? Siesta Beach's sand consists of 99% quartz.

Quartz possess birefringent property which can be examined under polarized light microscope. It can provide an important clue for mineral identification. The pictures below are the sand collected from the camping trip alone the Gulf of Mexico.

Siesta beach sand at 20x under polarized light microscope. The size of the
sands are small and uniform. Under polarized light microscope, they exhibit
various colors due to different thickness and orientation.

Siesta beach sand at 50x under polarized light microscope

Crescent beach sand at 20x under polarized light microscope. Like the
sands collected from Siesta beach. The sizes of the sand crystal are small
and uniform.

Turtle beach sand at 20x

Sand collected from Henderson Beach, FL

Sand collected from Gulf State Park, AL

The Beach Sand of the Gulf of Mexico

2011-06-25T23:56:00.200-04:00

The beaches on the Gulf of Mexico are famous for their crystal clean water and sugar white sand. Siesta key beach received numerous awards for its soft, clean, pure-white sand. The Siesta beach ranks the number one beach in Dr. Beach's top 10 beach list again this year. Unlike most beaches that are composed of crushed shells, rocks or lava, the powdery sand found on the Siesta Beach is pure white and finer in texture than most refined sugar. Harvard University's geology department found the sand of Siesta Beach was 99% pure quartz.
During the spring break, we had a chance to visit several beaches on the Gulf of Mexico on a camping trip. We collected some beach sand from each park on the trip (Figure 1): The Gulf State Park, Alabama, Henderson State Park, Florida and Siesta Key, Florida (We visit all three beaches on the key: Siesta, Crescent and Turtle beach). I check them out on my microscope. Are they as good as claimed?

Figure 1. Beach sand collection sites on our camping trip

Figure 2. Sand collected from Siesta Beach, FL

Of all beaches on our camping trip, the sand on the Siesta beach appears to be the whitest. The sand is also very soft to touch. It has powdery feel when I rub them between my figures. The images under the microscope explain the the color and soft touch. The sand crystals are almost all quartz and completely transparent with very few impurities. The small and uniform in size also explains the powdery and soft touch. (Note: The images under the microscope are sparkling. It looks much better than the pictures show - To be fairly compared with other sand specimens, I fixed the ISO and exposure time while taking the picture. The whiteness of the sand caused the picture to be over-exposed.)

Figure 3. Sand collected from Crescent Beach, FL

On the same key as the Siesta beach, the Crescent beach is slightly to the south of Siesta beach. The color of the beach sand is almost as white as the sand on Siesta beach and have the same soft, powdery feel. Under the microscope, they appears almost the same as the sands from Siesta beach. The slightly more yellowish color is barely noticeable unless I put the picture side by side.

Figure 4. Sand collected from turtle beach, FL

The turtle beach is located on the south end of the Siesta key. The sand is very dark and coarse. There are plenty of sea shells on the beach. There is no surprise to see that there are plenty of sand made of sea shells. There are very few quartz crystal found in the sand collected from Turtle beach.

Figure 5 Sand collected from Henderson State Park, FL

Henderson State Park beach is located between Pensacola and Panama city. The area is famous for its Emerald green ocean. The sand is sugar white but the sand crystal is more granular than the sand collected from Siesta or Crescent beach. Like the Siesta or Crescent beach, the sand is almost completely consist of transparent quartz. The quartz crystal is also larger.

Figure 6. Sand collected from Gulf State Park, AL

The color of the beach on Gulf State Park, AL appears to be more yellowish. The sand is still be but not as powdery as the sand found on Siesta or Crescent beach. The sand crystals appear to have more impurities and less transparent.

Figure 7. Sand collected from Gulf State Park playground

Interesting sand we found in the playground of the Gulf State Park. There are purple, green and blue particles in the sand. Out of curiosity, we collected some sand from the play ground and looked at them under a stereo microscope. They appears to be quartz but stained with different. The sands seem to have more round edges caused by the weathering. They appears to be different from the sand collected on the beach.

That's just about my general impression about the same. Can the number tell me the same story?

The whitenss appears to be consistant with the purity of the quartz crystal found in the beach sand. I took three pictures for each collection by randomly selecting three different areas of the sand specimen. The number of quartz crystals that are completely transparent, semi-transparent (milk white or yellowish) or none-quartz particles - nice summer project for my kids. Megan helped out a lot for counting the crystals.

Figure 8. Counting the number of completely particles in the same specimen. The picture shows the sand specimen collected from Gulf State Park, AL. The completely clear quartz crystals are striked with green lines while the impurities are circled.

The beach sand collected from Siesta (1142/1149; quartz particles/all particles), Crescent (1144/1152), Henderson State Park (268/270) and Gulf State Park (446/449) beach all have over 99% of quartz. The percentage goes down to 93% (419 / 449) for Gulf State Park if I only included completely transparent quartz crystals. The sand from Turtle beach is completely opposite of others. It contains only 2.5% of quartz (3/114).

Figure 9 Measure the size of particle with TSView image microscope

image acquisition and measuring software

The granunality of the sand can be measured by the size of the sand particle. Using microscope calibration slide to obtain the conversion factor between pixels and micrometer, I can convert the size of the sand particles in the digital image from pixel to micrometer. I sampled the particles by drawing a line diagnally and measure the length of any particles across the line. The average size of the sands from Siesta and Crescent beach (197 and 194 um, respectively) are the smallest among all specimens. Followed by Gulf State Park and Henderson State Park (386 and 509 um). The tutle beach sand has the largest average crystal size among all parks (900 um).

What lives in the flower pot's drainage pan

2011-06-16T21:53:00.002-04:00

The drainage pans of the flower pots can easily accumulate water after daily watering or heavy rain. The nutrients rinsed down from the drainage hole of the flower pot provides good source of energy for microorganisms. It's semi-enclosed space offers year-round environment suitable for microorganism to nurture. What do I found it the drainage pans of my flower pots?

Two rotifers were trying to gather foods using cilias on the top of the coronas.

The drainage pans of the flower pots are perfect breeding place for mosquitos.

Chucky Gal Mountain Field Trip

2011-06-06T22:44:00.003-04:00

We have looked forward to returning to North Carolina for rock hunting since last year's visit to hiddenite gem mine. The school was just ended couple weeks ago. We can't miss this GMS field trip to Chucky Gal Knob. It's a two and half hours drive from metro Atlanta. Due to the high elevation, it was as hot as Atlanta.

Waiting at the intersection of Hwy 64 and Buck Creek

for other rock hounds to show up.

There are green rock (not showing due to the light condition)

all-over the place. The surface is porous caused

by the weathering.

Ruby corundum crystals can be found in the green
Smaragdite.

Another photos of a Ruby Corundum crystal in the

Smaragdite. The color of the rubies can be anywhere

from pink to purple. There are also some very bright green

minerals found in the matrix but I am not sure what they are.

Picture show the layer of weathered surface and green

interior of the smargadite.

Soap stone (Talc)

Another commonly found rock is soapstone. They are light and form layers. They are very soft to touch and very smooth to touch.

Some soapstone exhibit green color tone.

Some soapstones are more black in color.

Megan seems to be more interested in the stone in

white color. In the picture is the milky quartz.

Some Smaragdite on milky quartz.

Although we have not found any ruby of good size but the sprinkles of ruby found in the green Smaragdite already making us very excited about the trip (Some member did find a strip of ruby of finger width.). Maybe we will hit the jackpot next time.

Infestation of Asian Pear

2011-05-24T06:28:00.009-04:00

Two years ago, my Asian pear trees (Niitaka and Hosui) were infected with fireblight. They were almost die. Couple applications of fertilome fireblight spray (21% Streptomycin) during budding and flowering seemed to take care of the problem this year. Unfortunately, I wasn't pay much particular attention when the tree was starting to produce fruit. I was just about to thin the fruits when they reach the nickel size. I found some ugly tiny fruits.

The hosui pears were bubbled up to form a very strange shape.

Some were completely infested

Some fruits were producing white tubes and orange dust

Cut the fruit open and place in under my stereo microscope.
It appears that there are some sort of insect infestation in isde.

The white tube under stereo microscope.

I sent the pictures to Georgia Gardener. I received the response. It appears that the white tubes are from some sort of fugal infection similar to Cedar - Hawthorn rust (The fungus develops on a cedar tree and then infects hawthorn trees growing close by. After growing on the leaves, orange, dusty spores are released that colonize nearby cedar trees.) After research a little bit, the same type of rust fungus also form similar life-cycle between the juniper and pear/apple. I also received the response from the Gwinnett county agriculture extension about the insect infestation. They might be codling moth or Asian fruit moth. I am not sure which one. I am going to set up some trap to collect some moth during the summer.
It looks like I will have smaller crop this year. The infection is serious. It almost wiped out three quarters of all my fruits. I will remember to treat the tree when my tress start setting fruits next year.