Q. Why is the Columbia Basin such a good location for agriculture?
A. Many things are required for good crop growth, but some factors, including water and soil, often are limiting factors. The fact that we are so fortunate to have access to good, clean irrigation water is such a big factor. Maintaining our ability to access this water and having a good water system set up is important to this area. This allows producers to use center pivot irrigation. Center pivots are an efficient economical way to irrigate fields that are about 100 acres in size. Center pivots also allow producers to manage their water in ways that maintain ground water quality that are not possible through flood irrigation.
Q. I want to apply a shredded bark mulch to control weeds in my landscape, but I’m not sure how much I’ll need. What do you recommend?
A. When bark is used alone on the top of soil for weed control in the landscape, a 3- to 4-inch layer of shredded bark provides the best control. Less bark will not provide adequate weed control; more bark can smother plant roots. One cubic yard of bark will provide you with a 4-inch layer of bark over 80 square feet or a 3-inch layer over 100 square feet.
Keep bark six inches away from the base of woody plants so that the bark doesn’t keep the crown too wet and lead to rot.
Q. I would like to buy some ladybugs to release into my garden. What is the life span of a ladybug?
A. The life span of insects depends on many factors, including weather, season, shelter and food resources. Ladybugs released into a garden likely will not last more than one season. They may reproduce and have offspring that could be found the following year. However, insects such as ladybugs often will disperse if adequate food sources are not available. So, if you release them in your garden with no prey (aphids), they probably will leave before you get any benefit from their release.
Q. My grapes have started to form leaves. Can I still prune them?
A. Grapes should be pruned when they are dormant, however, you will not sustain any damage by pruning now.
-- Questions should be called in to the WSU Extension offices in Kennewick at 735-3551 or Pasco at 545-3511.