- Author: Lynn M. Sosnoskie
There are TWO upcoming weed science extension days in the San Joaquin Valley this April.
The first will be held on the 2nd of April at the Kearney Agricultural Research and Extension Center in Parlier (9240 South Riverbend Road, Parlier CA 93648) and the second will be held on April 11th at the Westside Research and Extension Center in Five Points (17353 West Oakland Avenue, Five Points, CA 93624).
The meeting at the Kearney Center will focus on rangeland, turf, and tree and vine systems while the meeting at the Westside Center will focus on agronomic crops, ROWs, and tree and vine systems. Both meetings will open with hands-on weed ID and nozzle...
- Author: Lynn M. Sosnoskie
You just KNOW that some plants are considered weeds. Their common names give them away. They sound awful. Giant hogweed (Heracleum mantegazzianum). Ripgut brome (Bromus diandrus). Devil's claw (Proboscidea lutea). Smellmelon (Cucumis melo). Itchgrass (Rottboellia cochinchinensis). Dog-strangling vine (Cyanthum rossicum).
Others...well, others seem more benign. Even sweet. For Valentine's day I present to you nine weedy plants with lovely names. Enjoy...
1. Tree-of-Heaven (Ailanthus altissima). How celestial (Sigh...). How divine (Sigh...). How invasive (sigh...wait, what?). Tree-of-heaven is a deciduous tree, native...
- Author: Lynn M. Sosnoskie
Recently I was asked to help identify prostrate knotweed (Polygonum aviculare) that was collected from an alfalfa field. Admittedly, the tough and wire-like specimen that was submitted to me at the end of autumn didn't much resemble the succulent seedlings that I have often observed emerging in tree and vine systems in early spring. Consequently, I dug out my 'Weeds of the West' and 'Weeds of California and Other Western States' books and double-checked with colleagues to ensure that my ID was accurate. This post is meant to build on that effort and describe the morphological traits that are characteristic of prostrate knotweed and how to differentiate the species from a similar-looking weed, spotted spurge (Euphorbia...
- Author: Lynn M. Sosnoskie
Why is weed identification important? Simply stated, because not all management strategies are equally effective against all weed species. The weed community present in a given field, orchard, or vineyard may be comprised of species that are differentially sensitive to different herbicide modes of action or physical control practices. Even closely related species may respond differently to different herbicide active ingredients. For example, according to UC IPM crop management guidelines, metribuzin and S-metolachlor can provide partial control of yellow nutsedge (Cyperus esculentus) but no control of purple nutsedge (Cyperus rotundus). Consequently, to develop effective weed control programs, managers should be aware...
- Author: John A Roncoroni
- Posted by: Gale Perez
[From the Spring issue of the UC IPM Retail Nursery & Garden Center News and the Pests in the Urban Landscape blog]
“I hate crabgrass!” is a common lament I've heard from residents during my 35 years in UC Weed Science. However, four out of five times, the weed people are actually referring to is not crabgrass, but bermudagrass or dallisgrass. So why does knowing the name of the weed matter? It...