The generous rains of winter have enticed a magnificent array of native wildflowers to spring forth from our often parched soils. March saw local legions of blooms that sprinkled, or even carpeted the earth. As of mid- March, Raven’s Nest Nature Sanctuary hosted over 30 species of blossoming native plants—a bedazzling diversity of mostly annual species with a few perennials thrown in for good measure. Each type of flower has co-evolved with its pollinator(s), helping to maximize the chances for successful fertilization of its ovules or eggs. Once produced, seeds take center stage with a surprising variety of ways to sow themselves across the land.
No doubt you’ve observed that spring can be a rather windy time here in the Sky Islands. Wild temperature changes can generate significant winds, which has not gone unnoticed by seeds looking to hitch a ride. Velvet ash throws out green flowers that clearly have not evolved to lure in native pollinators. Instead, this riparian tree relies primarily on the wind to disperse its pollen. Likewise its samaras, or winged seeds, are carried away from the parent tree by gusts once they have matured.
On the other end of the size scale are diminutive silver puffs—yellow, dandelion-like flowers in the aster family. Once pollinated, silver puffs produce achenes, parachute-like structures conducive to wind transport. No need for wings. The silvery scales of the seeds tend to catch on passing breezes, helping to disperse them to new sites. Other “wind-surfer” wildflower seeds also glide themselves to new sites in kindred fashion.
A sort of mechanized seed travel is also characteristic of other species, like the California or Mexican Poppy. The name “poppy” derives from the fact that the plant’s seed pods become spring-loaded once they ripen. They catapult their seeds out from the plant that birthed them. This creates a rather meager dispersal zone, at least compared to the travel power afforded by the wind. Our native fairy duster sub-shrubs similarly possess seed pods that dehisce, or split, with considerable force, “springing” the seeds away from home.
Other spring wildflowers employ animals as their prime method of seed dissemination. Perhaps these “clingers” are the most obvious category of wildflower seed dispersers, owing to their admittedly annoying habit of sticking to our clothes. The aptly-named stickleaf not only will readily attach its seeds to your socks and/or pants but also throws its namesake foliage in for good measure. Peering down at your now adorned garments, inhale deeply while trying to avoid any expletives. After all, you hold the future of these meager seeds on your very person. Other animals, such as desert cottontails and coyotes, also help to ferry stickleaf seeds around, allowing them to reach new territory. Joining them are various members of the borage or forget-me-not family, such as popcorn flowers. The seeds of this family are covered in coarse hairs that readily latch onto passing animals. If a wide-ranging animal, such as a white-tailed deer is the seed conduit, then it’s easy to see how “clingers” may even surpass “wind-surfers” in their ability to broadcast their seeds. Even more so when a bird consumes a seed that it later defecates out in a still viable condition. Long distance seed dispersal accomplished via gastronomy!
Any species of native wildflower that lives in, or whose seeds are somehow transported to a local arroyo or other waterway, may well enjoy a liquid trip courtesy of a flood event. These “floaters” can then reach far-flung locales, even founding new populations at times. Prickly poppies often grow in arroyos and hence must be beneficiaries of this method of dispersal.
Throw in a final category of “fallers”—a species of plant whose seeds merely plummet to the ground via gravity—and you more or less have the main methods of seed scattering covered: wind, ballistic, animal, water and gravity.
By hook or by crook, by land or by “sea,” by sheer gravitas, seeds find their way to where they must in an effort to proliferate. When our wildflower show has passed, the seed pageant has just begun. Look for these fascinating seeds. Admire their multitude of forms. See if you can guess as to their main method of travel. Most of all, encourage native wildflowers in your backyard. Set the stage for an “invasion” of these seeds, allowing them to reclaim lost ground as they march through time.
Vincent Pinto and his wife, Claudia, run RAVENS-WAY WILD JOURNEYS LLC, their Nature Adventure & Conservation organization devoted to protecting and promoting the unique biodiversity of the Sky Islands region. RWWJ offers a wide variety of private, custom-made courses, birding & biodiversity tours. Visit ravensnatureschool.org