Yellow nutsedge found a good home in warmer areas of California and purple nutsedge is sometimes present as well. In bare-ground soils the depth of roots and tubers varies from few inches to two feet, but we wanted to know how does yellow nutsedge grow and produce tubers in beds covered with plastic mulch. Plasticulture in increasingly common and almost all strawberries, fresh market peppers, tomatoes and some other crops on the coast are grown on mulched beds. In previous studies we have identified barriers that are dense enough to resist sharp tips of nutsedge shoots and are either water resistant or protected from wetness with low density mulch. The barriers were more economical than hand-weeding, gave nearly 100% control of nutsedge...

Producing 85 percent of the nation’s strawberries, California growers urgently need alternatives to methyl bromide fumigation if they are to maintain yields. Methyl bromide has been phased out for all but critical uses because it depletes ozone in the upper atmosphere.

UC scientists now report that use of totally impermeable film in strawberry fields can improve the effectiveness of a widely-used MB alternative known as 1,3-D (1,3, dichloropropene). Use of the film reduces the amount of 1,3-D needed to maintain yields, while lowering field emissions overall.

The strawberry industry is highly dependent on soil fumigation to control pests and maintain high yields. The methyl bromide alternative, 1,3-D, can be used...

Weeds can be introduced to new areas from a variety of natural and human-influenced sources.  Seed transport on vehicles or equipment can be a very important mechanism of spread. 

The WSSA article below focuses on transport of invasive weed seed on recreational and work vehicles in rangeland areas but the same concepts hold true in agricultural or residental situations.  Have you ever run a mower or tiller through a weedy area and then looked closely at the amount of vegetative matter (and potenially seeds) on the mower deck or in the nooks and crannies of the machine?  All that junk (and  seeds) can fall off in subsequently visited areas and introduce new weed species or biotypes into the new area.

It is a good...

When talking about chemical weed control, a lot of different terms are used to describe the chemicals and application techniques being used.  Some are terms are pretty straight forward while others are a little more specific or specialized.  I thought it might be a good time to run through a few commonly used terms.  Feel free to add (via comments) any important terms that I miss and I’ll try to edit them in over time.

Preemergence (or preemergent) herbicides.  Herbicides that are applied before the target weed germinates and emerges.  Many, but not all, preemergence herbicides have little activity on existing vegetation.  Instead, they act on the roots or shoots of newly germinated seeds – often killing the...