Saturday, February 26, 2011

Taming Bamboo and Forcing Forsythia

While visiting Merida on the Yucatan peninsula in Mexico, we stayed at a hotel with rooms so tastefully decorated that one could turn in any direction and see a composed scene.

One object that put to good and decorative use what in Princeton is often an overly aggressive plant was this wrapping of dried bamboo cuttings into a vaselike pattern.

The same effect can be rendered with cuttings of forsythia, which have the added benefit this time of year of opening their flower blossoms after a week indoors.

Slow To Learn About Turtles

It was a Tuesday night, and the Keeper of the Playmobile Village had another entry to write in her 5th grade science journal. She retrieved a long-ignored old turtle shell from the back porch, and though the shell did not look to be a particularly promising door to discovery, we were taken by surprise. Who knew, for instance, that the scales (called scutes) that form a pattern on the turtle's back are actually skin that covers some 60 bones comprising the shell? Certainly not we who had until now been largely unmindful of turtle lore. Or that the dark color of turtle shells helps them absorb the sun's heat when basking on a log. Or that the way the seams between the scutes extend pretty much straight across the back of this turtle (photo) from side to side make this an eastern painted turtle that has long since lost its colors. Its surviving offspring are likely hibernating in some nice mud at the bottom of a lake or stream right now, dreaming of basking in the sun through summer days, and living to the ripe old age of 55, as painted turtles have been known to do.

Friday, February 25, 2011

Nature Walk This Sunday, Feb. 27, 1pm

Another cabin fever relief walk, to see if there are any signs of spring stirring at Pettoranello Gardens, Community Park North woods, Tusculum meadows, and Witherspoon Woods. Will likely include a visit to Devil's Cave if trail conditions allow. We'll try to steer clear of mud, but dress accordingly just in case. Meet at the Community Park North parking lot, on Mountain Ave. next to 206, at 1pm. Walk sponsored by Friends of Princeton Open Space.

Thursday, February 24, 2011

Blueberry Bees

More buzz on bees. Got into a conversation the other day with a botanist who shifted careers to study native bees, partly out of fascination and partly because so little is known about them. We got to talking about blueberry bees, which use rapid wing beats to shake pollen loose from the flower. Here's a description I found via an internet search:

"The southeastern blueberry bee (Habropoda laboriosa) is so named because it is native to the southeastern US and forages primarily on blueberry (Vaccinium spp.) plants. It resembles a small bumble bee (Bombus spp.) and is abundant in blueberry orchards throughout its range. Blueberry plants are most effectively pollinated by sonication and the southeastern blueberry bee is very efficient at this. The bee grabs onto a flower and moves its flight muscles rapidly to release the pollen. The bee's face is then covered in pollen, which is inadvertently deposited at the next flower on which the bee forages." (nbii)

The frequency of the wing beats determines whether the pollen is shaken loose. Since honey bees don't use sonication to shake pollen loose, they have a harder time pollinating blueberry flowers.

Something to look for when the blueberry flowers come out this spring. He also said that native bees can be safely petted, which I had heard before, in reference to bumble bees. Since I've never tried it, please don't take this as a recommendation, but it is interesting to consider that fascination and respect may be more useful responses to bees than a blanket fear. Here's a post, found via an internet search, that includes a video of bumble bee petting, described as a relaxing activity.

Sunday, February 20, 2011

A Backyard B&B For Wildlife

This is a bittersweet story sent to me by my good friend Brownlee. She had long had groundhogs living under her patio deck, but recently noticed some new and different tracks in the snow.
Turned out a pair of foxes had decided the underside of the deck would make a fine "bed and breakfast."

Looked like a fine arrangement for all, except the groundhogs, but Brownlee started noticing signs of mange on one of the foxes. A call to Princeton's animal control officer led to trapping the fox and taking it to the Mercer County Wildlife Center, where it unfortunately could not be saved. The other fox will be trapped this week, and hopefully is healthy enough to respond to treatment. According to Brownlee, the mange-causing mites die off after a month without a host, allowing the treated fox to be returned to the same location. As one could guess, the loss of fur due to mange can be especially hard on wild animals in the winter.

Some informative websites on mange, which includes various species of mites that afflict a wide range of animals, can be found here and here. Thanks to Brownlee for the photos.

Saturday, February 19, 2011

Herrontown Woods Walk

We had a great walk in Herrontown Woods a week ago. The abundant snow brightened the scene, and there were lots of bright questions, including why the common names for trees are as they are. Why are oaks called red or white or black? And why is there a dog in dogwood? In the midst of a towering forest, sometimes the simplest questions can leave a walk leader stumped. Even my assertion that the trunk of a musclewood tree looks muscular was received with considerable skepticism by a charming young girl named Meadow, who wanted most of all to head off-trail and climb some of the boulders beckoning as we headed up into the Princeton ridge. Not a bad idea, that, but we ended up staying on trail and more or less on topic, discussing the ways to know a tree by its bark, or craning our necks to see last year's blossoms on the soaring tulip poplars. (Note: For some interesting cultural history of dogwood, and speculations on the origins of its name, click here.)

One curious sighting was a young tree, perhaps 15 feet tall, whose bark had been stripped clean off from the top all the way down to about our level, where shreds of bark still hung on. The exposed wood was smooth and shiny, as if carefully burnished by someone on stilts. Various theories were put forth: lightning, perhaps, or the rubbings of a wayward giraffe. I doubted it was lightning.

On the way back, we stopped by the Veblen farmstead, where the boarded up home of the famous mathematician still sleeps, dreaming mysterious dreams and waiting for someone to solve the riddle of its future.

Some Buzz On Native Bees

Rutgers entomologist Rachael Winfree gave an information-packed talk on native bees at DR Greenway this past Thursday. Here is some of the information I packed for the trip home, with apologies for any bruising of the truth that might have occurred in-transit. Rachael has a very useful downloadable brochure on the subject of native bees and the sort of plants and nesting habitat they need (link below).
  • Bees are some of the most beautiful animals on earth.
  • They're descended from wasps. Wasps feed animals--other insects, I suppose--to their young, while bees are vegetarian, raising their young on pollen. Bees are also better pollinators, being more hairy.
  • There are about 400 species of native bees in NJ (I was guessing around 100), out of about 4000 native species in the U.S.
  • The natives are grouped into the Mellitidae, Andrenidae, Halictidae, Colletidae, and Megachilidae. Honey bees, which are not native to America, are in the Apidae.
  • The peak diversity of most kinds of animals and plants can be found in the tropics, but peak diversity of bees is in xeric (dry) temperate zones, such as Arizona. They are most diverse in unwooded areas.
  • A "univoltine" bee produces only one generation per year, while multivoltine bees have multiple generations.
  • Bees, depending on species, can overwinter in any stage, from egg to adult.
  • Most adults live only a few weeks.
  • Some bees come out in early spring and then go dormant through summer, fall and winter. Those may be the ones that are specialized to feed off of spring ephemerals (woodland wildflowers that sprout early to take advantage of the sunlight before the trees leaf out).
  • Pollen supplies protein, nectar provides sugar.
  • Female bees are better pollinators than males, which are smaller and less hairy.
  • Just as there are parasitic birds like cowbirds that leave their eggs in other bird species nests for raising, there are also parasitic bees that use the same strategy.
  • The blueberry bee specializes in pollinating blueberry flowers. (Turns out they are one of the single generation per year bees. An interesting description of their pollination technique can be found here.)
  • A heterogeneous landscape, such as can be found in towns and suburbs, helps provide a progression of flowers throughout the growing season (whereas our dense woods may only provide flowers in the spring, if the spring wildflowers are intact.)
  • That honeybees are proving susceptible to various maladies is not surprising, given that they are part of a monoculture approach to farming. Honeybees are trucked all over the States to pollinate crops, be they almonds in California or cranberries in the northeast. Huge expanses of one crop create locally a boom and bust cycle, in which flowers are abundant for only a brief period each year, making it impossible for a resident bee population to survive. Trucking in honeybees is the only way to insure pollination. 
  • Community Collapse Disorder, in which the adult honeybees disappear from a hive, leaving only the young, first appeared in 2006. The cause remains unknown, though it may be a combination of stresses caused by the varroa mites that first reached this continent in 1990, pesticides such as imidacloprid, miticides, a virus or bacterium, and poor nutrition. 
  • It's not clear if honeybees have affected native bee populations in the U.S, though some evidence suggests their competition can reduce native bee numbers.
  • There is no monitoring of native bee populations in the U.S, so it's hard to tell if there are any trends in native bee populations.
  • There are some endangered bee species in NJ, but it wasn't clear if there's anything that can be done locally, such as grow particular plants, to help them recover.
  • She suggested a couple websites. To plant bee-friendly habitats, check out her brochure called Native Bee Benefits. For bee identification, DiscoverLife is a popular website. BugGuide is another helpful site for getting identifications.

Tuesday, February 15, 2011

Free Talks On Bees and Butterflies

This is part reminder, part update. The talk this Wednesday is about the many species of native bees hereabouts.

Rachael Winfree, "The Business of Bees"
Wednesday, February 16, 6:30 pm
Rick Mikula, "Butterflies: Their Beauty and Perils"
Thursday, March 10, 2011, 6:30pm
Note: This is the new date for the program that was "snowed out" in January
These programs will be held at DR Greenway's Johnson Education Center, One Preservation Place, Princeton. All programs are open to the public, and registration is helpful by calling 609.924.4646

Telling North and South in a Snowbound Forest

There's a prairie wildflower called Compass Plant that orients its leaves north and south, which could prove handy sometimes in a featureless sea of grass. A couple weeks ago at Community Park North, the snow on the trees was performing a similar service. Look northwards and the tree trunks are bare.
Look to the south (at the north sides of the trees) and the tree trunks are coated with snow that the sun couldn't get to.
The snow also makes it easier to see the dense miniature forest of ash tree seedlings, just a few feet high, poised to seize the daylight when the evergreens begin to falter. This is not your normal New Jersey piedmont forest.

Thursday, February 10, 2011

Nature Walk this Saturday, Herrontown Woods, 1pm

I'll be leading a nature walk to explore Herrontown Woods on the east side of Princeton this Saturday at 1pm. The walk is open to the public, and sponsored by Friends of Princeton Open Space. To reach the parking lot for the park, drive out Snowden Lane. Just before reaching Herrontown Road, turn left down the road across from the Smoyer Park entrance and drive to the end.

The woods are filled with light this time of year, and the trees are easy to identify by the grain of the bark and the patterns of the twigs. Donated to Mercer County long ago by the famous mathematician, Oswald Veblen, and his wife Elizabeth, Herrontown Woods includes the Veblen's house, cottage and barn, where Einstein was a frequent visitor. The buildings have been boarded up for eleven years, and will likely be torn down if action is not taken soon to save them. 

Wednesday, February 02, 2011

White Pine

 One way to identify white pines around town is by all the branches they lose in heavy snows.
Identity can be confirmed by pulling several clusters of needles off the stem and counting how many are in each cluster (fascicle). White pines have needles grouped in clusters of five--the same number as there are letters in "white".

One can also determine the age of a white pine by counting the whorls of branches on the stem. One whorl is produced each year.