Excerpts from Jim Conrad's
Naturalist Newsletter
from the March 30, 2014 Newsletter issued from the Frio Canyon Nature Education Center in the valley of the Dry Frio River in northern Uvalde County, southwestern Texas, on the southern border of the Edwards Plateau; elevation ~1750m (~5750 ft); N29.62°, W99.86°; USA
DRUMMOND'S ONION
Common along US 83 north of Uvalde were the pretty wildflowers shown above. At first I thought they might be camas lilies or wild hyacinths, but camas lily/wild hyacinth flowers are arranged in a more slender raceme, while these flowers have their stems, or pedicels, arising close together atop the raceme stem, or peduncle. When hyacinth-type flowers are arranged like those in the picture, you need to crush one of the plant's leaves and smell. Very likely the odor will be that of onion, and that's what this plant is, a wild onion of the genus Allium. A close-up of a flower appears below:
Lots of onion species are recognized -- between 550 and 700, depending on your expert. The Flora of North America lists 96 for our continent.
In our area we have two very similar wild onions species: Allium canadense occurs throughout the eastern half of North America, and; Allium drummondii is limited to the south-central states, extending into arid northeastern Mexico. Both species often produce onion bulbs, or "bulbils," in the flower cluster itself, but our roadside plants had none. Our pictures show ALLIUM DRUMMONDII, also known as Drummond's Onion, Wild Garlic and Prairie Onion.
In general, Drummond's Onion is larger and more robust that Allium canadense. Otherwise they're so similar that technical features are needed to distinguish them. One technical difference is that on Allium canadense the small, papery bracts, or scales, immediately below each flower cluster bear 3-7 pink veins, while on Drummond's Onion there's only one vein. I didn't know about that trick when I was photographing so I can't show it. However, looking at flower pictures of both species, it can be seen that the petal-like sepals of Allium canadense are slightly narrower, especially at their bases, than those of Drummond's Onion, and our flowers match the latter.
Both species arise from acorn-size onion bulbs, and those onions are not only edible but delicious if properly prepared and used. Many indigenous American groups ate them, and at certain seasons may have used them as a main food source, for often Wild Onion grows in huge populations.