- Author: Tunyalee A. Martin
It’s that time of year again when hot weather fuels the creation of ozone, or smog. Some pesticides emit volatile organic compounds (VOCs) that contribute to ozone formation. Using pesticides that release VOCs may be restricted in certain California locations between May 1 and October 31.
If you plan to apply a pesticide, use the Department of Pesticide Regulation’s VOC calculators to determine emissions from fumigant and nonfumigant pesticides. Get there by clicking on the Air Quality button at the top of each treatment table in the UC IPM Pest Management Guidelines: Rice.
Simple steps can minimize the release of VOCs into the air:
- Use pesticides only when necessary.
- Decrease the amount of pesticide applied if appropriate.
- Choose low-emission management methods.
- Avoid emulsifiable concentrate (EC) formulations and fumigants.
Ozone, or smog, is caused by mixing VOCs, nitrogen oxide, and sunshine. High levels of ozone can harm people and crops. Regions in California that do not meet federal or state air quality standards for ozone, called nonattainment areas, may restrict the use of pesticides that release VOCs.
I was asked the other day what do immature tadpole shrimp (TPS) look like. Young TPS look pretty much like the older ones, just smaller. The very first instar, which remains inside the egg for a few hours, looks somewhat different, but you are not going to see this instar in the field with the naked eye. A few hours later they molt and look more like regular TPSs. Here's a picture of a few of them a few days later swimming belly up. Notice the rice grain floating next to them for size comparison.
I just read an article from the latest edition of California Agriculture: “Nitrogen fertilizer use in California: Assessing the data, trends and a way forward”. The article compiles data about inorganic N fertilizer use by major crops in California and compares data from the 1970s to the 2000s. Rice is one of the crops included, accounting for 10% of the total N fertilizer used by the 33 crops considered. Two points jumped at me. First, the article found that “experts” believe growers apply more N fertilizer than growers report applying. The authors used the UC Davis Cost and Return Studies as the experts’ opinion, and grower surveys conducted by the USDA for growers input on N fertilizer rates.
The second point is that the average N fertilizer rate for all 33 commodities in the study increased by 25% from 1973 to 2005. In the case of rice, for the same time period, the N fertilizer rate increased from 86 to 130 lbs N/acre (52% increase). The authors caution that these numbers shouldn’t be taken in a vacuum, that yield increases should be considered. I calculated just that: if you consider the 5-year moving average rice yield, you find that the lbs of N fertilizer used per lb of rice produced hasn’t changed from 1973 to 2005, it’s 0.02 lbs N fertilizer/lb rice.
The University of California is in the process of hiring a Cooperative Extension Rice Specialist. Two applicants have been selected as final candidates, and as part of the interview process, they will be giving an Extension Seminar. I would like to invite rice growers and PCAs to attend the seminars. The candidates will be talking about you, and wish to be selected to the Rice Specialist position to serve you. Your presence at the seminars is very important!
Both seminars will be held at Lundberg Family Farms Multi-Purpose Room.
March 26th, 10:00-11:00 AM – Dr. Bruce Linquist – “FURTHER STRENGTHENING LINKAGES BETWEEN RICE RESEARCHERS AND PRODUCERS”
March 28th, 10:00-11:00 AM – Dr. Ryan Van Hayden – “OUTLINING A STAKEHOLDER DRIVEN AGENDA FOR RICE RESEARCH AND EXTENSION IN CALIFORNIA”
See you there!
I uploaded the 2013 Rice Grower Meetings presentations to the UC Rice Project website. Let us know if you have any questions!