- Author: Robert Kourik
A little something that a friend wrote for gardeners, but is applicable to farming. You can read more of Kourik's stuff at:http://www.robertkourik.com/tidbits.html
Some garden suppliers now offer beneficial microbial and fungal inoculants to “boost” the soil's fertility. Some products tout the benefits of mycorrhizae inoculants for plant roots.
I contacted soil scientist Dr. Phillip J. Craul, a soil scientist and Senior Lecturer at the Graduate School of Design at Harvard University with the question: “what do the new packaged microbial and fungal products offer gardeners?” His immediate response: “I'm going to be frank, most of the time the home gardener doesn't need to fuss with (inoculants). Such products are only helpful in special cases where you're working with sterile material; (however), most of the biological analyses show enough organisms are usually present under artificial conditions to repopulate the soil—even in urban areas.”
In some cases, here with California native plants, inoculation with mycorrhizae had less new shoot growth—measured on a dry basis—than native soil.
“New Research in the Use of Mycorrhizaefor Nursery Production” by Lea Corkidi Mike Evans and Jeff Bohn, Tree of Life Nursery September 2008.
Furthermore, the soil's vast complex of biota defends its own territory from “invading” microorganisms. Existing microbes and mycorrhizae can be very good at fending off inoculants. According to Martin Alexander, “Microorganisms inoculated into non-sterile soil lead to poor growth and often the seeded species is eliminated in a period of days or weeks...(due to) a rivalry for limiting nutrients, the release by one species of products toxic to its neighbor and direct feeding of one organism upon a second.”
In a study with established willow oak (Quercus phellos), red maple (Acer rubrum) and pin oak (Quercus palustris) trees it was found that “Our data indicated no apparent measurable growth benefit [to estblished sreet trees], under the terms and conditions of this research, to inoculation with a commercial mycorrhizal fungal product unless combined with fertilizer.” “Mycorrhizal fungal Inoculation of Established Street Trees” by Bonnie Appleton, Joel Koci, Susan French, Miklos Lestyan, and Roger Harris. Journal of Arboriculture 29(2): March 2003.
Here's the Fall newsletter of Topics in Subtropics, and it is on time. Winter hasn't started yet, but get ready.
And the topics are:
- Real-Time Sensor for Early Detection of Citrus Huanglongbing (HLB)
- The 2016 International Citrus Conference
- UC Riverside Scientists Evaluate Trunk Injections of Pesticides for The Management of Ambrosia Beetles in California Avocados
- An Overview of Mango
- Water Based Latex Paint as a Means to Track Ambrosia Beetle Activity on Infested Trees
- Author: Sonia Rios
When: December 15, 2016
Where: USDA-ARS U.S. Salinity Laboratory - Loctated on UCR Campus 450 W. Big Springs Road, Riverside, CA 92507 https://campusmap.ucr.edu/
Time: Registration, light breakfast & coffee will be served at 8:00 AM, program from 8:30 – Noon
Cost: FREE Please register at : http://ucanr.edu/survey/survey.cfm?surveynumber=19550
Moderator: Sonia Rios, Subtropical Horticulture Farm Advisor, UCCE Riverside & San Diego Co.
8:30 AM – Welcome, Donald Suarez, U.S. Salinity Laboratory, Director
9:05 AM – “Avocado salinity management: Response of different rootstocks”- Donald Suarez Ph.D., USDA-ARS Salinity Laboratory Director
9:25 AM - “Grape Management in southern California - Carmen Gispert Ph. D. Area Viticulture Advisor, UCCE Riverside
9:55 AM – “Wine Grape production under saline conditions” - Donald Suarez Ph.D. USDA-ARS Salinity Laboratory Director.
10:10 AM - Break- light refreshments & snacks
10:30 – Noon - “Introducing Passion Fruit as a New Crop to Southern California- Cultural aspects and salinity effects” & Field Tour - Jorge Ferreira, Ph.D., Research Plant Physiologist, USDA-ARS, US Salinity Lab.
For more information, please Contact: Sonia Rios, UCCE Subtropical Farm Advisor: firstname.lastname@example.org
Donald Suarez, USDA Salinity Laboratory Director: email@example.com, 951-369-4815
redcThe hills have been dry for a long time, and the long dry fall is bringing animals into the avocado groves that normally stay out in the hills. They want the green cambium of trees and the moisture it provides. And especially rodents will have a field day in the well-maintained orchards.
Gophers are not usually a problem in mature avocados. They will often chew the bark below ground. Ground squirrels when they get hungry can go after just about any part of the tree, trunk branches and fruit. Voles or meadow mice will go after bark about 2 inches above ground. Rabbits can take out bark up to a foot above ground. This bark damage often leads to the yellowing of the canopy and if damage is extensive enough, wilting of the canopy. Growers don't normally see the damage until they see the wilted tree and start looking for the problem. If healing along the margins of the damage is occurring, it means it was damage that was done previously. If margins are still ragged, it means the beasts are still enjoying the tree. Trapping, poisons and a busy Jack Russell terrier are all effective, especially if used together. Voles especially like mulch around the base of the tree, and should be pulled away a foot to 18 inches. They make tunnels thought the mulch which then becomes a diagnostic for identifying the cause.
It's not just avocados that are ravaged by these animals. Citrus is like candy to them and then there's all those acres and acres of almonds that have been planted.
Avocado canopy collapse. Why? Check the tree out. See the red squirrel feeding stations in the background?
Damage that is healing over.
On a recent trip, we saw Diaprepes Root Weevil damage on avocado. It was feeding on the leaves, tattering them. The problem with this pest is that it also feeds on the roots, weakening the tree and opening it up to disease, such as Phytophthora. This adult beast about measures about ¾ inch long and the larvae are bigger, about an inch long. They are hard to kill when they are in the ground. They have a host range of 270 plant species including citrus, strawberry, papaya and lots of vegetables species. It's already found in parts of LA, Orange and San Diego Counties. If you see it, call the local Ag Commissioner. https://www.cdfa.ca.gov/Plant/pdep/target_pest_disease_profiles/Diaprepes_PestProfile.html
Treatment options are listed in the IPM Guidelines
You don't want this in your orchard.
Diaprepes feeding on avocado (Tim Spann)
Damage to citrus root system.