- Author: Chris M. Webb
Ventura County UCCE Staff Research Associate Maren Mochizuki shares with us more information about yellow nutsedge, and what is being done to help minimize the problems it causes to local growers.
Managing yellow nutsedge costs local growers many thousands of dollars per year (see previous blog posting on yellow nutsedge for more information). Nutsedge is sharp enough to poke through plastic mulch installed on strawberry and vegetable beds. Once a shoot germinates through plastic, it can produce underground storage structures for reproduction (tubers) so that even if the shoot is removed, many tubers remain to sprout into new plants.
Nutsedge through plastic
To block shoot germination and prevent the production of more tubers, we (Oleg Daugovish, Ventura County UCCE Farm Advisor and Maren Mochizuki, Ventura County UCCE Staff Research Associate, in collaboration with Reiter Affiliated Companies) installed mechanical barriers underneath the plastic mulch of strawberry beds, including Tyvek homewrap, landscape weed barrier mat, and a layer of recycled paper roll between two layers of plastic.
All of these barriers prevented germination of yellow nutsedge in commercial strawberry fields compared to control beds with no barriers, but the plastic/paper/plastic treatment has the lowest cost per acre. Minimizing production of yellow nutsedge tubers reduces weed-crop competition and costly hand-weeding, improving the grower’s bottom line.
- Author: Chris M. Webb
Today our Staff Research Associate, Maren Mochizuki, will share with us a glimpse inside a recent day as our office works to better understand the growth patterns of the yellow nutsedge.
Yellow nutsedge is a difficult weed to control because the plant produces new shoots via underground stems called tubers (similar to a potato); a few plants can turn quickly into an infestation! Costly and labor-intensive hand weeding has been the only means of management because current herbicides are not effective.
Strawberry bed with yellow nutsedge
To understand the underground growth of this weed, we (Oleg Daugovish, Ventura County UCCE Farm Advisor; Emmanuel Gonzalez, Ventura County UCCE Lab Assistant; and Maren Mochizuki, Ventura County UCCE Staff Research Associate) sliced a cross section of an infested strawberry bed. We were hoping to answer the following questions: How deep are the tubers? About how many tubers are produced from each shoot?
After cutting the cross section and pushing it onto a bed of nails to hold it, we were able to lift it onto the truck tailgate and drive it to a water source to wash a few cubic feet of soil from the nutsedge underground stem/root system. We were surprised to find that the tubers were not as deep as we expected (no deeper than 8 inches) and we counted several hundred tubers from our cross section, or about 3 per plant.
Yellow nutsedge tubers
The research team has another multi-year study using mechanical barriers such as layering plastic mulch, then paper, and another layer of plastic prevents germination of yellow nutsedge in strawberry beds as they continue to develop ways to handle this problematic weed. The mechanical barrier study will be featured in tomorrow’s blog posting./span>