The drought-related pressures on the Colorado River system that have been impacting the entire basin and region for 23 years have slackened briefly due to the wet winter in 2023 that included a good snowpack in the mountains, better rainfall throughout the basin, and improved flows into the river. The current water level at Lake Mead on Hoover Dam is 1,068.25 ft. above sea level on 3 January 2024. That level is 160.75 ft below full pool of 1,229.00 ft. (Figure 1).
In mid-December 2023 representatives from each of the seven Colorado River Basin states met in Las Vegas, NV during the annual Colorado River Water Users Association conference. The focus of current discussions among the basin states is to negotiate a new compromise for the guidelines of use under conditions of water shortage. These new guidelines will go into place at the end of 2026. The immediate goal is to draft proposals by March 2024.
The negotiations are incentivized by having the opportunity for the post-2026 guidelines being developed by the basin states themselves as opposed to litigation or legislation. A major concern driving this process among the basin states that basin state representatives should be able to do this better than turning the process over to people and entities that have less direct familiarity with the situation and no real “skin” in the game.
The 1963 decision by the Supreme Court of the United States in of the Arizona v California case directed the federal authority on the management of the Colorado River to the Department of the Interior and the Bureau of Reclamation (BoR). However, the basin states have the chance to negotiate their future management plans on the Colorado River. If they fail to do so in the allotted time, the process will be managed by the federal government.
The basic water budget challenge is based on the following basic statistics:
Some notable progress is being made for conservation of Colorado River water with agreements among lower basin states and tribes that will conserve more than 1.5maf/year through 2026. For example, California water agencies have recently agreed to conserve up to 643,000 acre-feet/year through 2025. The Quechan Indian Tribe has reached an agreement with federal water managers to save up to 39,000 acre-feet/year through 2025. Arizona has agreed to conserve up to 348.00 acre-feet/year through 2026. All these temporary agreements are being supported with federal funding.
With agriculture responsible for 70% of the diversions on the Colorado River, these negotiations are extremely important for the future of agriculture in this region and our capacity to support high population densities that are now common and rapidly growing.
These types of negotiations are certainly challenging in dealing with a limited water supply and a lot of demand. There are many competing interests involved. Yet, we are confident that the representatives we have will be able to work this out and come to a set of functional agreements.
Frost and freeze damage affect countless fruit and vegetable growers leading to yield losses and occasionally the loss of the entire crop. Frost damage occurs when the temperature briefly dips below freezing (32°F).With a frost, the water within plant tissue may or may not actually freeze, depending on other conditions. A frost becomes a freeze event when ice forms within and between the cell walls of plant tissue. When this occurs, water expands and can burst cell walls. Symptoms of frost damage on vegetables include brown or blackening of plant tissues, dropping of leaves and flowers, translucent limp leaves, and cracking of the fruit. Symptoms are usually vegetable specific and vary depending on the hardiness of the crop and lowest temperature reached. A lot of times frost injury is followed by secondary infection by bacteria or opportunist fungi confusing with plant disease.
Most susceptible to frost and freezing injury: Asparagus, snap beans, Cucumbers, eggplant, lemons, lettuce, limes, okra, peppers, sweet potato
Moderately susceptible to frost and freezing injury: Broccoli, Carrots, Cauliflower, Celery, Grapefruit, Grapes, Oranges, Parsley, Radish, Spinach, Squash
Least susceptible to frost and freezing injury: Brussels sprouts, Cabbage, Dates, Kale, Kohlrabi, Parsnips, Turnips, Beets
More information:
Presentation given at 2021 ASABE Annual International Meeting on the development and evaluation of a novel, band steam applicator for controlling soilborne pathogens and weeds in lettuce. Band-steam is where steam is used to heat narrow strips of soil to levels sufficient to kill soilborne pathogens and weeds (140 °F for 20 minutes). Development of a band-steam applicator that applies steam in 4" wide by 2" deep band centered on the seedline is presented. Two trials investigating the use of band-steam for controlling Sclerotinia lettuce drop and weeds in lettuce were conducted. Trial results were promising. Highlights included finding that treatment with steam provided better than 85% weed control, and the unexpected result that crop yields were improved by more than 24%. Energy requirements were high and treatment costs were more than $650/acre. Band-steam may be a viable technique for controlling soilborne pests in high value vegetable crops such as lettuce if the significant yield increases found in this study can be realized.
To watch presentation click: A Novel Band-Steam Applicator
When I think about Lipid Biosynthesis Inhibitor herbicides, Post (sethoxidim) and Select (clethodim) come to my mind. A great description of these type of herbicides can be found at the Section VI of the Arizona Pest Control Advisor (PCA) Study Guide. They say a good teacher can explain complicated things in a simple way. Please read this explanation by Barry Tickes:
“These herbicides are known as ACCase inhibitors because they inhibit the production of acetyl-coenzyme A carboxylase (ACCase) which is an enzyme needed in the first steps of lipid or fatty acid production. Lipids are needed in the production of new membranes which, among other things, are needed in the production of cell walls. These chemicals move from the foliage to the growing points, only kill grasses, and have very little soil activity. Grasses stop growing immediately and slowly turn chlorotic or red and die usually in 7 to 21 days. These products are used to selectively kill grasses in broadleaf crops".
|
Classification |
Common |
Commercial |
Arizona crop |
|
Aryloxphenoxy |
fluazifop |
Fusilade |
Small grains, |
|
Cyclohexanediones |
sethoxydim |
Poast, Segment, |
Alfalfa, cotton, |
You need to see this .. time lapse photography shows the symptoms of Poast herbicide to wheat.
Results of pheromone and sticky trap catches can be viewed here.
Corn earworm: CEW moth counts remain at low levels in all areas, well below average for this time of year.
Beet armyworm: Trap increased areawide; above average compared to previous years.
Cabbage looper: Cabbage looper counts decreased in all areas; below average for this time of season.
Diamondback moth: DBM moth counts decreased in most areas. About average for this time of the year.
Whitefly: Adult movement beginning at low levels, average for early spring.
Thrips: Thrips adult counts reached their peak for the season. Above average compared with previous years.
Aphids: Aphid movement decreased in all areas; below average for late-March.
Leafminers: Adults remain low in most locations, below average for March.
