- Author: Ben Faber
INTERACTIVE IRRIGATION MANAGEMENT TO REDUCE THE LEACHING OF NITROGEN
IIMRLN PROGRAM
The program purpose is to reduce the amount of nitrogen leached from farms with the goal of enhancing surface and groundwater quality
Participants will be selected based on:
• potential for nitrogen leaching and proximity to nitrogen-impaired waterbody
• potential for water-use and fertilizer use reductions
Participants will receive:
• a free NIM station, irrigation and nutrient data reports, and access to real-time soil moisture data
• free access to irrigation and nutrient management technical assistance and recommendations
Free Zoom Workshops – just click the link to participate on the date and time indicated!
Hear details from Jodi Switzer - Farm Bureau VC, Ben Waddell - Fruit Growers Lab, Israel Camacho - AGQ Labs, Eryn Wingate - Tri-Tech Ag, and Jamie Whiteford - VCRCD
Monday October 19, 12:00 - 1:00 pm. To attend this remote workshop click HERE
Thursday October 22, 9:00 - 10:00 am. To attend this remote workshop click HERE
Friday October 23, 12:00 - 1:00 pm. To attend this remote workshop click HERE
Friday October 23, 1:00 - 2:00 pm. To attend this remote workshop click HERE
For program questions contact JamieWhiteford.vcrcd@gmail.com, 805-764-5132. For program information or to complete an IIMRLN application click: IIMRLN webpage
Subtropics Snapshot: The Mexican Date Industry
Noé Ortiz-Uribe1, Ricardo Salomón-Torres1, Robert Krueger2
1Universidad Estatal de Sonora; 2USDA-ARS, Riverside, CA
The crop practices used in commercial date production in Mexico are mostly the same as those used in the United States, since the main growing areas in the U.S. are close to the San Luis and Mexicali Valleys and have similar climates and soils. Some companies have plantations in both countries.
Propagation is mainly by offshoots. The main cultivar, ‘Medjool', produces many offshoots. Propagation from tissue culture is uncommon at this time, although recently there have been some plantings of tissue culture-derived palms from the U.S. and Qatar. These have not yet been field tested for performance compared to offshoot plantings.
Fertilization is provided mainly for N-P-K. In sandy soils, fertilizer is delivered via irrigation systems, and amendments for improving soil water retention are widely used. Organic production areas are small, but slowly increasing. Various farms are being certified since the market of this category of products gives better prices for the organically grown dates. Plantation practices differ based on the irrigation technique. Limited water supply is forcing irrigation to turn to pressurized systems; however, flood irrigation is the main method of water delivery. Flood-irrigated fields are leveled with laser equipment. In sandy desert areas, where flood irrigation is impractical, no leveling is required, and the use of drip irrigation with pressure-compensated drippers allows small slopes and dunes in the production field. In Baja California Sur, irrigation in modern commercial plantations is delivered by dripping systems, whereas in Coahuila, only the flooding technique is used.
The process of pollination in commercial plantations is carried out artificially, while in the oases it is performed naturally by the wind. Pollination takes place once the inflorescence is open by late February or early March. For ‘Medjool', thinning of the bunch follows pollination. Some 15 to 20 flowering strands are cut from the center of the inflorescence in April and in May fruits are removed so that there is a separation of 1 inch between remaining ones, leaving 12 – 18 fruits per strand. This practice improves fruit quality and reduces alternate bearing. A concurrent activity to the thinning process consists of the tying of the bunch to the closest leaf in a position for easy access during the following activities. This supports the bunch and reduces the number of broken fruit stalks. Sacs of mesh fabric are placed covering the fruit raceme to avoid damage from birds and insects. This activity is carried out when the fruits turn to a yellow color at the khalal stage in July to August.
Pest presence on date palms in Mexico is not significant, but there are various potential threats. Insect pests, such as various species of nitidulid beetles, have been detected infesting ‘Medjool' dates in the Mexicali valley, and red mites can cause production losses. No research has yet been done to characterize the incidence of these pests in the region. The South American palm weevil, Rhynchophorus palmarum, has been detected in cities close to the production areas; therefore, a program for monitoring its potential presence is needed.
Date palm diseases in commercial production areas are not reported yet, but some plantations in both the San Luis Rio Colorado and Mexicali regions show a few palms with symptoms similar to those of Fusarium. Since this disease can be devastating to date palms, these palms need to be closely monitored. Additional information regarding potential disease problems needs to be developed for the Mexican date-producing areas.
Vertebrate pests of date palms include squirrels and gophers. A potential vertebrate pest not found in the U.S. is the monk parakeet (Myiopsitta monachus), which makes its nest on the palms and feeds on the dates. The monk parakeet has been observed in garden palms and other plants in areas near date production in both Sonora and Baja California.
Harvest of ‘Medjool' starts in August and finishes by October. Dates are harvested from the ground or by climbing into the crown with young, short trees. Harvest of taller trees uses forklifts fitted with circular platforms that are used to elevate the crews to crown. Date fruit are harvested into circular trays consisting of fishing net over a metal form, and then lowered to the ground and placed into 2-inch deep plastic trays.
The date growing industry has the potential to contribute to the economic development of the northwest of Mexico, since there are not many other regions in Mexico that can grow high quality dates. Date growers are improving date cultural practices, and it is very possible that yields increase from the current average of 7.9 ton/ha to 10 ton/ha in the next 5 years. The main obstacle for this industry is commercialization and export. Currently, there is only one integrated company that exports the packaged fruit to other countries. Training and financing are required so that small and medium producers are better organized and form co-ops for packing and marketing of their products. In order to stimulate internal consumption, it is necessary to widely disseminate the health benefits generated by the consumption of dates. It is necessary to carry out more research on date palms in order to improve the current methods of cultivation, to be prepared for possible future pests, work with practices to optimize the use of water, and develop new products derived from the date. Likewise, research to take advantage of date palm agricultural residues, such as the extraction of oil from the seed, or use as biofuel or livestock feed is needed.
Note: This article was adapted from a longer, refereed paper. Ortiz-Uribe N, Salomón-Torres R, Krueger R (2019) Date palm status and perspective in Mexico. Agriculture 9, 46. doi:10.3390/agriculture9030046
Read more at: http://ceventura.ucanr.edu/Com_Ag/Subtropical/
- Author: Ben Faber
California Avocado Society's
2020 Annual Meeting
Co-Sponsored by UCCE and
CA Avocado Commission
The 105th Annual Meeting will be Online
October 21, 2020 (Wednesday)
Starting at 9 AM
Speakers and Topics
Dr. Gary Bender - High density
Lance Andersen/John Burr - Water
Jim Davis - Lace bug
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- Author: Ben Faber
Evaluating claims of new products that could potentially improve yield and tree health is a daunting task. Every week I get calls and literature from people promoting fertilizers and techniques that "resist insects," "reduce salt levels in the soil," "increase crop quality," "release that natural fertility of your soil," and numerous other claims. There just is not enough time in the day to approach each and every one of these materials or techniques, even though some may, in fact, be promising.
So what does a grower do? You hear about a new product. It only costs $20 an acre to apply. Might as well fly it on all 50 acres. But then, how do you know it has done anything? What results do you have to compare it with? Last year's yield which was miserable? We know how variable avocado yields are, so last year's harvest may not be a good comparison.
When we conduct field trials, we assume a clear comparison is available to test the effects of the treatment. With field trials, there are usually small plots, repeated several times (at least three), and arranged in an apparent haphazard (random) fashion. The reason is threefold: 1) to account for variability in the field, 2) to prevent a systematic bias in favor of one treatment over another and 3) to see if differences in treatments are due to chance or to the superiority of the treatment.
How are observational trials different from replicated one? The big difference is that they are not replicated. Each treatment occurs only once, so we have no measure of the natural variability in the field or trees. As a result, we risk thinking we have a difference due to treatment which is actually due to field variability. Without replication there is no way to tell.
Let's examine this replication idea a little more closely. We had a frost trial where we applied copper or a water control spray to young trees in November. Copper is a noted bactericide and the idea was to control the frost-nucleating bacteria. Forty trees, randomly spaced in the orchard were sprayed with either a dilute copper spray according to instructions or water alone. We evaluated frost damage to the trees in January. The first counts showed 40% frost damage with the copper spray and 60% with the water alone. Great. Let's go out and spray the whole orchard next year with copper. However, successive counts showed 50% frost damage with the copper and only 30% from the water. In the end, there was no significant difference to trees that had been sprayed with either material.
These results show the natural variability in biological systems and demonstrate the disadvantages in looking at results from a non-replicated trial based on a single year. This becomes even more important when interpreting information from a trial site different from your own. If every grower sprayed a non-replicated treatment at their own ranch, the risk of coming to the wrong conclusion about that treatment at each location is still 50%. Just like flipping a coin. Is that worth spending money on?
As each of the variables (soil type, irrigation quality, management, etc.) increases, the risk of making a poor decision about a product or practice increases, as well. You can see that there are difficulties associated with relating information from a non-replicated trial based on a single year of data at a different location to your own situation.
How does someone go about evaluating a new practice or material at home without going through all the complications of a complicated research trial? Mary Bianchi, retired Farm Advisor in San Luis Obispo and I came up with a little checklist.
- Be conservative in your approach and critical observations. Resist the urge to spray the whole grove. Leave something, so that a comparison can be made. Preferably run a side-by-side comparison.
- Use consistent farming practices across all areas of the trial.
- Compare the new practice to one which is a standard for your operation.
- Don't bias your results by implementing the new practice where it stands to have the best effect anyway. For example, don't spray boron on the trees that always give a good yield.
- Run the test more than one year and in more than one location, especially if the new practice is costly.
- Talk to the industry and use the experience of others in different locations as a check on your own experience. A good place to swap ideas is at the California Avocado Society/CA Avocado Commission/University of California Cooperative Extension sponsored bimonthly meetings.
Research does not need to be complicated, but it needs to be thought out before hand with consistent data collection and given time. And time is critical, especially for nutrient studies and with a tree like avocado, that has a prolonged bloom with alternate bearing and usually more than one crop at a time. The effects of application timing at a given rate might not be determined for several years of crop yield. Persistence is the key to experimentation. Unless it's a pesticide trial, do you see results in the first year.
- Author: Ben Faber
UCCE-UC IPM Biologics Educational
Webinar Series
Free Events
Nov 10 – So many products, so much confusion
Effective use of biostimulants in agriculture
Patrick Brown, Plant Sciences, UC Davis
3 - 4:15, 1 CCA CEU
Nov 18 – Biological plant growth regulators:
Experience, facts and future
Michael Rethwisch, UCCE Advisor, Riverside Cpunty
3 – 4 PM, 1 CCA CEU
Dec 3 – Biostimulants from a regulatory perspective
Nick Young, Senior Environmental Scientist
CDFA – Fertilizing Materials Inspection Program
3 – 4 PM
Dec 9 – Synergistic or antagonism?
Integrating crop biologics into IPM
Surendra Dara, UCCE Advisor, San Luis/Ventura Counties
3 – 4 PM, 1 DPR & 1 CCA CEU
Contact: Zheng Wang, UCCE Advisor, 209-525-6822
zzwwang@ucanr.edu