Invasion

© Dave Spier

There's a wildflower that's trying to take over much of the country from Alaska to Georgia and all of the northeast to Quebec. (The USDA has a range map on their website.) It tolerates shade and crowds out native plants. Deer are repulsed by its garlic odor and flavor, making it a clever defense in hindsight. It's a prolific seed producer and if that's not enough, it releases chemicals that inhibit the growth of other nearby plants, particularly native tree seedlings. We're talking about Garlic Mustard (Alliaria petiolata, = A. officinalis and two other synonyms), a true member of the mustard family and relative of such familiars as cabbage, broccoli, cauliflower and of course, other mustards including the one used in the condiment.

Garlic mustard is a biennial. It takes two years to fully mature and go to seed. The first year, it produces only a few rounded to heart-shaped leaves as it concentrates on growing a root system. The second year, new and larger leaves (more triangular and coarsely toothed around the edges) emerge. A stem averaging one to two feet high sprouts a cluster of small, white flowers, each with four petals. These produce long, thin seed tubes that eventually dry, split and release two rows of numerous black seeds to start the process over again.

This invasive weed was brought here from Europe and Asia in the 1860's, probably to be used as a potherb. Various recipes can be found on the internet and involve using young leaves and flowerbuds and to a lesser extent flowers and seeds. This is another case of "eat it, if you can't beat it." From the looks of it, there are far more plants than we could possibly eat, so the next alternative is to pull them up by their roots, put them in a black plastic bag in the sun and eventually bury them in a long-term compost pile or otherwise dispose of the plants depending on the regulations in your neighborhood. Don't let them lay around. Even if you dry the roots and let the plant die, the seeds continue to mature. Mowing does nothing to stop the invasion because the roots quickly grow new stems and leaves and then flowers at a lower height. The seeds can lie dormant up to five years and then sprout, so the best alternative may be to trash the seed heads.

In its native Europe and eastward to India and western China, 68 insect species and seven types of fungi feed on the garlic mustard. None of these controls are present in this country. To make matters worse, deer eat our native wildflowers instead, making more room for the garlic mustard to flourish.

In Defense of Plants sent me information on a book called Garlic Mustard - from Pest to Pesto. If you have any suggestions for controlling garlic mustard, or recipes to share, please send them along with any corrections, comments and questions to northeastnaturalist@yahoo.com or connect through my Facebook page and photo page. There's also a community-type page for The Northeast Naturalist. Other nature and geology topics can be found on the parallel blogs Adirondack Naturalist and Heading Out.

Photographing Violets (revised)

Photographing Violets -- © Dave Spier

In the past, our front yard under the big shade trees was loaded with wild blue violets, but this year there are very few. At first I thought it might be a result of last year's drought, or too many fallen leaves left on the lawn over the winter, or who knows what. Now that the violets are in full bloom I've found them again, but they've "migrated" to other parts of the lawn, but still in partial shade under trees. I suspect the ants dispersed the seeds and started new colonies. I had hoped to further experiment with photographing the flowers, but the weather isn't cooperating. I may have to make do with this series of images from 2006 when the violets "peaked."

The initial backlit shot of the backlit group of blue violets... 
Note the distracting bright background.

Aside from a straight-on documentary shot that I may start with, I'm partial to backlighting for its artistic potential. The second photo is actually the first grab-shot to set the scene. I'm flat on the ground with the camera on a special "tripod," actually little more than two crossed boards in a "T." The obvious problem is that the bright, sunlit background is very distracting as it competes for the viewer's attention. The simple solution is to set the camera on self-timer, then walk around to the other side of the violets and cast a large shadow into the background. (The alternative is to have a friend help you.) Usually holding a jacket or shirt to the side works well to create a shadow, and sometimes a notebook or clipboard will suffice for more intimate closeups. The result is the third image. Had I been more alert, I would have noticed the bright grass blades on the right side. Being my yard, I easily could have clipped them. Oh, well. The final image (the opening photo at top) somewhat "solved" the problem with a little cropping. On the down side, there's a backlit violet leaf at lower left. Somewhat distracting, but again, oh, well.

Casting a dark shadow across the background eliminates bright clutter. 
(Even if it's out of focus, the original backdrop competes and distracts.) 
This shadow mimics situations encountered in real life when everything comes together naturally. 
In retrospect, a bit of fill-flash [or a weak reflector] would have added a touch of detail 
to the dark petal areas. 

In case you didn't notice it, look closely at the second photo along the top edge right of center. Notice the two pieces of lint on the sensor? I was using the original 5D which had a serious problem with attracting dust and lint to the sensor, even with the sensor turned off when changing lenses. (To somewhat deal with the issue, that particular camera body, with a cleaned sensor, is now dedicated to the 17-40mm, my widest-angle zoom, to take advantage of the full-frame for landscape work.)

Technical details: The first three images were shot on aperture priority with a Canon 100mm macro at 1/6 sec., f/16 and ISO 100, initially spot-metered. There was no exposure compensation and no fill-flash. Color space is Adobe RGB (required by my main agent at the time). In addition, my default white balance is "cloudy" because I prefer warmer tones for my style.

A straight-forward documentary shot of wild blue violets, 
not necessarily the same clump as the other photos. 
Note the distracting clutter in the background at this typical viewing angle. 
Manual exposure at 1/125th sec., f/16 and ISO 100 
using a Canon 5D with 100mm macro and macro twin-flash...

Corrections, comments and questions are always welcome at northeastnaturalist@yahoo.com or connect through my Facebook page and photo page. There's also a community-type page for The Northeast Naturalist. Other nature and geology topics can be found on the parallel blogs Adirondack Naturalist and Heading Out.

Crocuses

Last Saturday, the first two purple crocuses (croci if you prefer) appeared in our front yard. No, they didn't actually open that day. They just poked their spiral-wound heads above the leaf litter to test the cold winds. Sunday was a different story. A patch of a neighbor's front yard turned purple as his crocuses greeted the warmer temperatures. By Tuesday, my white and yellow crocuses also fully opened. I noticed them on my way across our yard to work in the vegetable garden.
 

I'm surprised my crocuses lasted as many years as they have. They came with the house when we bought it in 1984. Their numbers have dwindled and the large patch in the front yard is down to one or two. I'm not replacing them with more crocuses as I let the yard go native, but neither will I dig out and discard perfectly healthy, beautiful, non-invasive plants that signal the arrival of spring. You might say I'm attached to them.

Crocus is a large genus in the iris family. A particular species (Crocus sativus, similar to the garden variety in the photos) is the source of saffron (from the Arabic or Old Persian word za'faran), a spice derived from the dried, aromatic stigmas. The saffron crocus is a sterile species that does not exist in the wild, so it requires continued human help to survive. I remember my grandmother using it as a poultry seasoning, but beware - saffron is now the most expensive spice in the world. It's very labor intensive and each flower yields only a tiny amount.
  

Corrections, comments and questions are always welcome at northeastnaturalist@yahoo.com or connect through my Facebook page and photo page. There's also a community-type page for The Northeast Naturalist. Other nature and geology topics can be found on the parallel blogs Adirondack Naturalist and Heading Out.