Mike McGee grows Christmas trees in El Dorado county and has been using stump culture on his 19 acre Choose n' Cut Farm for 36 years. According to Mike, stump culture reduces the time to harvest for a White Fir from 8-10 years to 5-7 years. One stump can provide as many as eight harvested trees.
If you want a Christmas tree from McGee Tree Farm, you'd better plan on getting it early. Located at 3,000 feet elevation
For those of you who think growing Christmas trees is as easy as planting a few conifers and forgetting about them, beware. Christmas tree production and stump culture takes work to produce a good looking tree. The cut, number of nurse branches, and selection of final tree sprout all affect the resulting success and tree quality. McGee goes back to each harvested stump in January and recuts the stump using a sharp saw to produce a clean cut. He then paints the stump using a 4 inch roller and an elastomeric coating, which is dense and will stretch. The coating helps to prevent the stump from rotting until the tree's nature sap overgrows it, sealing the stump.
The bigger the tree stump, the more nurse branches that are left. Typically this means leaving 10-12 branches around a white fir. New trees will grow up from either a nurse branch limb that turns up-not desirable due to the bend in the bottom- or a new sprout which will grow straighter, and is therefore more desirable than a tree grown from a turned up limb. The limbs fold up and shade the cut stump, nature's way of protecting the cuts that heal better when they have shade.
“Every tree is a perfect tree”, McGee once told me, who actively grooms his trees to keep the farm looking neat. Stump culture work is best done during the dormant season when branches are still pliable and green, before the summer heat. In this way, cut branches are easy to pick up off the ground by hand, before they are dried out and too prickly to handle.
“On my farm, everything is an experiment”, McGee told me. “Growers have to try it and find out for themselves. Maybe what works for me won't work the same for them.” Opening a week early this year to thin out the crowds during Covid-19, the full parking lot at McGee Tree Farm tells me this experiment is working just fine.
UC Cooperative Extension, UCIPM, and the Spray Application Pest Management Alliance Team, with support from California's Department of Pesticide Regulation (DPR) Pest Management Alliance grants program, have developed a comprehensive online course for calibrating air blast sprayers!
Co-authored by myself and my colleague Franz Niederholzer, UCCE Farm Advisor in Colusa/Sutter/Yuba counties, this unique course is for anyone involved in spray decision making in perennial crops (trees and vines). Calibration is the process of setting up, maintaining, and rechecking a desired spray volume, measured in gallons per acre. It is the basis for a safe and effective pesticide application and is used by every grower-conventional to organic-who uses pesticides in their crop to help manage pests.
The course is organized into 5 modules:
- Why proper calibration is critical for your operation's success.
- Equipment: Parts of an axial fan* air blast sprayer.
- The calibration formula-how to measure the variables and do the math.
- Spray drift: droplet size, fan speed, weather, and how to manage.
- Spray team communication.
*We are working on a venturi (air-shear) sprayer module option which should be available soon.
- 2.5 California DPR CE credits have been approved (2.0 other, 0.5 laws). You must complete all of the course modules and pass the final exam with at least 70% to receive your CEUs.
With the support of DPR's Pest Management Alliance grants, this course is now available for FREE, until December 31, 2020.
You must have an account first in eXtension campus (available without
Smoke taint in wine is defined as a lingering retro-nasal character (some describe as licking an ashtray-yeck!) and is not to be confused with “tobacco” flavors some grapes and wines may impart. White wines, which are less complex than reds, often show smoke compounds more since the offending smoke cannot "hide" in the oak or wine matrix. When you taste a wine, saliva picks up the smoke compounds with the other flavors. Interestingly, approximately 20-25% of wine drinkers can't pick up smoke in a tainted wine.
How does smoke taint a wine? When lignin, found in woody plants, is burned, volatile phenols (VPs) are released that absorb to grapevine leaves and berries. The VPs are absorbed through the berry skin and become BOUND inside. So, there are both FREE and BOUND volatile phenols in grapes affected from smoke exposure. For the wine industry, predicting smoke taint is tricky. The amounts of VPs present in smoke affected grapes are not related; there may be little to no
What's a grower to do? While washing ash off of fruit may help with flavors directly from ash, washing will not reduce smoke taint. And, so far, there are no known vineyard treatments (sprays) that have been shown to reduce taint. Spraying anything with a spreader/sticker adjuvant, even oil, during a fire event may even increase smoke taint uptake. Possibly the best thing a wine grape grower can do is get clear on their winery contract with relation to criteria for rejection, and insure their crop against possible losses, from smoke taint.
So far, most of the 2020 wildfires are far from foothill vineyards. And, since most of the taint research is related to "fresh" smoke (in close proximity to an active fire), I'm hopeful that 2020 foothill wines will escape with little smoke taint. Years ago, after the 2013 Rim Fire that burned in Tuolumne County, I visited Yosemite Cellars owners Cheryl and Ron Harms. They boldly made a Rim Fire Red with smoke tainted fruit from that vintage. Cheryl said for a time, it was a favorite with young wine drinkers. They loved the smokey flavor, reminiscent of an expensive Scotch, she said.
The Daane lab joins Houston Wilson and other researchers on a nationwide search to confirm the three cornered alfalfa treehopper as a red blotch vector and/or identify other insects that are spreading the disease. Part of that work includes sampling for suspect insects using the D-vac and yellow sticky traps in vineyards where red blotch spread is evident. The trap count information is used to understand the life cycles of these potential vectors. Wilson, who was one of several speakers covering red blotch research progress during my 2020 Foothill Grape Day, recently published a newsletter on his work of the seasonal ecology of the treehopper in North Coast vineyards. Our foothill monitoring will help us understand if the insect's life cycle is similar here as compared to what is known to occur in the cooler N. Coast.
And no, those vineyard fall colors are not a good thing! This is the time of the year when GRBaV symptoms become evident in red varieties in the vineyard-the characteristic red "blotches" on the leaves for which the disease is named begin to show in summer and become more visible as harvest nears and the season progresses. (Note: the disease affects both white and red varieties. In whites, the "blotches" are yellow and more difficult to see). While diseased vineyards turn red, healthy vines remain green, then gold, in fall.
Thanks to the hard work of those like McCalla and Flores, even during this time of the pandemic (and wearing masks while working outdoors in summer heat is not fun, let me tell you), we will get closer to solving the red blotch mystery.
Biological control is defined as any activity of one species that reduces the adverse effects of another species. Living organisms are the agents of biological control, and although we may think of ladybugs and lacewings when we hear the term, bacteria and fungi can be biological control agents too! Microbes can act as antagonists to other microbes, they can out-compete them for nutrients or space, or they can secrete products that inhibit their growth. In fact, many biologically based pesticides harness the products of microbes, (think Bt or Spinosad).
The target of this biocontrol search is a formidable one. Grapevine trunk disease is present in nearly every mature vineyard, shortening its life and productivity. Some have even referred to the trunk disease epidemic as the "next phylloxera," because the disease is so devastating to vineyards.
The disease is caused by several fungi, all entering the vine via spores carried by rain on pruning wounds. Esca (called measles for the spotting on the fruit), Eutypa dieback, Botryosphaeria dieback, and Phomopsis, are all considered grapevine "trunk diseases"-infection can run from the pruning wound all the way into the trunk. The disease weakens spurs and shoots, in some cases killing them. Yield and grape quality is decreased. Eventually, diseased vines
Since pruning wounds can be susceptible to infection for weeks after pruning, the recommended practices to prevent infection are to prune late, to "double" prune, that is, make an initial pass in winter leaving 12-14 inches-this can be done mechanically-and then come back closer to budbreak when rains are less frequent to do the final pruning cuts, and to apply fungicide "protectants" to pruning wounds. Growers should also remove all infected prunings from the vineyard, minimize stress to new plantings and carefully inspect new planting material to be sure it is free
Enter the Eskalen lab! A group of UC Davis students studying plant pathology under scientist Akif Eskalen to help solve agricultural plant disease problems! Akif has recently taken the position of UC Plant Pathology Specialist, replacing the late Doug Gubler, and we are so fortunate to have him! Under Akif's direction, Marcelo will be culturing probably hundreds of microbes collected from vines. He'll screen them in the lab, and, fingers crossed, he'll find a few that show promising biological control against canker. Maybe, just maybe, he'll find some foothill microbial gold. I'll keep you posted...