Thu, 24 May 2007 05:00:32 GMT

Frozen and Fresh

Like so much of the rest of North America, Missouri faced a late-season freeze after a mild February and March. Many of the trees brought out their flowers and leaves early, and it turned out to be too early.

The frost-blighted leaves above are still hanging from a pignut hickory tree in the western end of Roundrock. There were examples like this all around. Blighted by the unexpected cold, these overachievers paid a price. (I have a couple of trees in my suburban yard — a gingko and a river birch — that took a hard hit. They are only now starting to bring out some tentative leaves again.)

I’m told that this late freeze means a reduction in the acorn and nut crop this fall, but I’m not sure I believe that. Don’t acorns take a few years to develop, at least on most oaks? Well, we’ll see what happens.

Here is another scene nearby. This is also a pignut hickory, and these leaflets look happy and healthy, soaking up the sunshine on that warm April day when we were there. A native tree in its native ground will cope. I can still take cheer from it though.

Missouri calendar:

• Blackberry winter; a cold spell may occur, freezing blackberry blooms.

Posted by: Roundrockjournal      Read more     Source

Thu, 24 May 2007 04:56:22 GMT

By the wayside

Our desination last Sunday was a roadside cliff in northeastern Pennsylvania that my friend L. remembered from one trip some seven years before. To hear her describe it, it was a veritable hanging garden of moss and ferns and wildflowers, and she had jotted enthusiastic notes to that effect in the margins of her atlas. We looked for over an hour, and never re-found

Oh sure, we found the road she’d marked in the atlas, but it wasn’t the one she remembered. The cliff was neither as steep nor as wet nor as rich; she didn’t even recognize it. The road she’d been on then had been paved, she was sure of it, but this was potholed grav

We consoled ourselves with a visit to Rickett’s Glen State Park. Black-throated green and black-and-white warblers called from the tops of old-growth hemlocks, but my attempts to pish them down within camera range brought me nothing but chickadees and a redstar

On our way down the glen, we saw waterfalls and blossoming hobblebush; on the way back up, we saw crowds of painted trillium. They were right beside the trail, and it was hard to see how we’d missed them on the way do

Driving back on PA Route 118 toward Hughesville, we pulled off the road to examine an incredibly verdant north-facing cliff, thick with moss and ferns (see photo at the beginning of the post). It was obviously very unstable, though, because a couple tons of it had recently calved, and blocked most of the berm. Directly across the highway, the rock cut was dry and grassy, and someone had erected a roadside memorial: white cross with a blue bow at its center, ringed with artifical roses and rocks the same color as the cliff. Joe Young, 34, 2003. Banks of greater celandine were in flower a few feet away, an old-world poppy more striking for its foliage than for its yellow, cross-shaped bloo Posted by: Vianegativa      Read more     Source

May 23, 2007, 9:48 PM CT

4-leaf Clovers

I find four-leaf clovers frequently, even when not explicitly looking.

A number of find this "gift" extraordinary, and even though this mutation is reported to only occur once in about 10,000 clovers, getting lucky isn't as hard as one would think......... Posted by: Falaco Soliton      Read more         Source

May 23, 2007, 8:02 PM CT

Plants that produce more vitamin C

UCLA and Dartmouth researchers have identified a crucial enzyme in plant vitamin C synthesis, which could lead to enhanced crops. The discovery now makes clear the entire 10-step process by which plants convert glucose into vitamin C, an important antioxidant in nature.

"If we can find ways to enhance the activity of this enzyme, it may be possible to engineer plants to make more vitamin C and produce better crops," said Steven Clarke, UCLA professor of chemistry and biochemistry, director of UCLA's Molecular Biology Institute and co-author of the research study, would be published as a 'Paper of the Week' in the Journal of Biological Chemistry and currently available online.

"We hit on gold," Clarke said, "because we now have a chance to improve human nutrition and to increase the resistance of plants to oxidative stress. Plants may grow better with more vitamin C, particularly with more ozone in the atmosphere due to pollution".

Carole Linster, a UCLA postdoctoral fellow in chemistry and biochemistry and lead author of the study, discovered the controlling enzyme, GDP-L-galactose phosphorylase, which serves as the biosynthetic pathway by which plants manufacture vitamin C.

"Our finding leads to attractive approaches for increasing the vitamin C content in plants," Linster said. "We now have two strategies to provide enhanced protection against oxidative damage: Stimulate the endogenous activity of the identified enzyme or engineer transgenic plants which overexpress the gene that encodes the enzyme"......... Posted by: Erica      Read more         Source

Mon, 21 May 2007 16:03:17 GMT

Arisaema sikokianum

Almost every year I photograph the reliable and intriguing woodland plant Arisaema sikokianum — a few older photographs can be seen here. Its common names are generally a reflection of its Japanese origin: Japanese Jack-in-the-pulpit and, more romantically, snow rice-cake plant (link to Paghat's site with gardening information). It is also known as gaudy jack.

View more photographs of Arisaema sikokianum via the International Aroid Society.

Botany resource link: Stannous F sent me a note letting me know that the folks at Earth Science Picture of the Day have had a few plant-related photographs recently. Here are two: Xanthorrhoea australis (grass trees) in Brisbane Ranges National Park, Australia and a Boreal Forest Ring from the Thunder Bay, Ontario, Canada area. Posted by: Daniel Mosquin      Read more     Source

Mon, 21 May 2007 03:04:51 GMT

Chloraea magellanica

Thank you to Krystyna Szulecka, who is a frequent contributor on the UBC Botanical Garden Forums, for contributing today's photograph (original in this thread). Krystyna is associated with the FLPA nature photography agency, and you can see more of her excellent images by searching for “Krystyna” on the FLPA web site.

Krystyna photographed this porcelain orchid in Lanin National Park, part of Patagonian Argentina. Its occurrence here places Chloraea magellanica among the southernmost distributed orchids in the world. Posted by: Daniel Mosquin      Read more     Source

May 17, 2007, 7:27 PM CT

Colorado River streamflow history

An epic drought during the mid-1100s dwarfs any drought previously documented for a region that includes areas of Arizona, Colorado, New Mexico, Utah and Wyoming.

The six-decade-long drought was remarkable for the absence of very wet years. At the core of the drought was a period of 25 years in which Colorado River flow averaged 15 percent below normal.

The new tree-ring-based reconstruction documents the year-by-year natural variability of streamflows in the upper Colorado River basin back to A. D. 762, said the tree-ring researchers from The University of Arizona in Tucson who led the research team.

The work extends the continuous tree-ring record of upper Colorado streamflows back seven centuries earlier than prior reconstructions.

"The biggest drought we find in the entire record was in the mid-1100s," said team leader David M. Meko, an associate research professor at UA's Laboratory of Tree-Ring Research. "I was surprised that the drought was as deep and as long as it was.

Colorado River flow was below normal for 13 consecutive years in one interval of the megadrought, which spanned 1118 to 1179.

Meko contrasted that with the last 100 years, during which tree-ring reconstructed flows for the upper basin show a maximum of five consecutive years of below-normal flows......... Posted by: Erica      Read more         Source

May 16, 2007, 5:13 PM CT

Useful Traits in Wild Cottons

If you have Mom's smile, Dad's eyes and Grandpa's laugh, you might wonder what other traits you picked up from the genealogic fabric of the ol' family tree.

Researchers at the Texas A&M University System Agricultural Research and Extension at Lubbock are studying the family tree of cotton for much the same reason.

"Cotton genetic diversity has narrowed in recent years," said Dr. John Gannaway, Texas Agricultural Experiment Station cotton breeder. "A number of of today's successful commercial varieties share common parents and grandparents.

"A number of researchers believe today's varieties are flexible enough genetically to handle minor changes but lack enough diversity for really spectacular change. Aside from limiting fiber quality and yield potential, narrow genetics makes them more susceptible to insects and disease."

Gannaway and other researchers believe future progress in cotton breeding can only be achieved if sufficient genetic variability remains in global breeding stocks.

The mission of the center's Crops Genetic Research Facility is to investigate the potential of useful traits lying undiscovered in the gene pool or germplasm of obsolete and wild cottons contained in U.S., Russian and French cotton collections. These traits could help diversify the gene pool from which breeders draw new varieties in the future......... Posted by: Erica      Read more         Source

Wed, 16 May 2007 03:52:05 GMT

Foeniculum vulgare 'Purpureum' (tentative)

Botany Photo of the Day will have brief written entries on weekends, holidays and my vacations from April through September. I'm on vacation today. – Daniel

Thank you to Jacki of Oregon, aka jacki-dee@Flickr for today's photograph (original | BPotD Flickr Group Pool).

Read more about fennel via Gernot Katzer's Spice Pages. Posted by: Daniel Mosquin      Read more     Source

May 14, 2007, 10:44 PM CT

Remote Sensing Tools To Predict Bird Species Richness

Researchers at the Woods Hole Research Center, NASA Goddard Space Flight Center and the University of Maryland have taken a novel approach to studying biological diversity by making use of laser remote sensing (lidar). Lidar data provide unique measurements of the 3-dimensional structure of vegetation, an important aspect of habitat diversity. Habitat heterogeneity and complexity have been shown in a number of places to be directly correlation to animal species richness a more complex environment provides a greater number of ecological niches to be filled by different species. Using this basic principle, WHRC researchers examined the relationships between bird species richness and habitat metrics derived from lidar data acquired by aircraft. They then explored the efficacy of predicting bird richness and abundance based on these metrics. The first phase of this research, profiled in the current issue of Remote Sensing of Environment, focuses on results from study sites in the Patuxent Wildlife Refuge in Maryland.

As per Scott Goetz, a senior scientist at the Center who is leading the project, "Lidar is the most unique and exciting technology to come along in the past decade in the remote sensing research community. We now have the ability to characterize vegetation in three dimensions, and that has implications not only for biodiversity research but also for improved estimates of biomass and carbon stocks."........ Posted by: Erica      Read more         Source