- Author: Lynn M. Sosnoskie
A recent announcement for the Twentynine Palms (CA) annual weed show got me thinking about how we (okay...I...) view unwanted plants. As a weed scientist, I spend >99% of my time thinking critically about weeds...specifically, their biology, ecology and management. The remainder of the time, I am actually enjoying them as botanical specimens worthy of admiration. In honor of the Twentynine Palms Historical Society's 75th (75th!!!!!) annual weed show (November 7 and 8, 2015), I'm providing you with something completely different...a few of my photographs highlighting weeds in their own unique glory.
Enjoy.
- Author: Lynn M. Sosnoskie
It's the 4th of July!
Time for fireworks! (Yay!) Time for picnics! (Yay!) Time for parades! (Yay!) Time for weeds! (Huh? What?)
That's right, weeds. While it is true that many problem pest plant species were imported from Europe and Asia, a lot are also home-grown. Here's just a few facts about three interesting and native species: horseweed, Palmer amaranth, and poison ivy. Happy Holidays!
Conyza canadensis (Erigeron canadensis) a.k.a horseweed, marestail
Horseweed is an annual species native to North America that can now be found in Eurasia and Australia, as well. It can be found in all of the lower 48 states and much of...
- Author: Lynn M. Sosnoskie
When we think about weed control in crop production, we often think about 'short-term' result, i.e. weed control after 30 days, weed control after 60 days, weed control at harvest, etc. But weeds and weed control efforts in one crop can significantly influence the density and composition of weeds in following years. The carryover between commodities and seasons is accomplished via the weed seedbank, which serves, in my opinion, as the memory of crop production practices. Weed control successes and failures are reflected by changes that occur in this genetic reservoir. In good years, weeds are successfully controlled and few to no seeds enter the seedbank; in bad years, when weeds escape management strategies, rogue plants...
- Author: Cheryl A. Wilen
One point I always make is that the sooner you control annual weeds, the better. The reduces crop-weed competition, along with a host of other issues caused by weeds (we'll save that for another blog). But the real key to forward-looking weed management is to kill the weed before it produces seeds. Once seeds are produced, they contribute to the seed bank, pretty much ensuring that the weed population will be a continual problem.
But suppose you miss some weeds that are starting to flower but the flowers aren't open yet? I think most growers will just pull or cut the weed and leave it in or near the field.
I want to show you a time-lapse video I took. I cut the flowering stem off of an...
- Author: Lynn M. Sosnoskie
- Author: John Cardina
Introduction to the species: Abutilon theophrasti (commonly known as velvetleaf) is a summer annual weed native to Asia. For those not familiar with the species, plants are tall (to 1-2 m) and erect with green- or purple-colored stems that branch at higher leaf axils (Warwick and Black 1988). The leaves are heart-shaped and covered in soft hairs (hence the name 'velvetleaf') (Warwick and Black 1988). Pale yellow- to yellow-orange-colored flowers are borne singly in the axils of leaves or in small clusters on short branches in the plant canopy (Warwick and Black 1988). Seed capsules are cup-shaped, hairy and either brown- or yellow-colored (Warwick and Black 1986, Kurokawa et al. 2003). Individual...