Planting native plants/re-forestation should be the number one priority in the world today. For 2000 years, we've been cutting trees and over grazing the land with no thought of replanting. Only in the past decade or two have we become concerned with the destruction of our forests.
It is my belief that the ozone layer depletion and global warming are both directly related to the destruction of our forests. I believe that these trends could be reversed with an organized world-wide commitment to reforestation.
I'm not against cutting trees, but our forests must be managed. I witnessed the destruction of some of our Redwood forests in Northern California during the 1960s and when I questioned their practices, I was denied access to the area. I witnessed the destruction of hundreds of young Redwoods up to 10-12 inches in diameter in the process of their logging one giant Redwood that measured 11 feet across at the trunk.
I was told that they planted 50,000 seedlings per section, after they finished the logging, with a 5% survival rate. They have since attempted to establish Douglas Fir with little success and are now planting Ponderosa Pine.
This brings us to one of the problems related to reforestation -- watering options/techniques.
There are basically five watering options available, but generally no more than two or three in any given region. The five options are: hand watering, flood irrigation, sprinkler irrigation, drip irrigation and DriWater
It is imperative that we plant native plants since they should only require supplemental watering for a short time to get their root system established. Once established, they should survive on their own.
There are seven major factors that will influence our choice of options. They are: water source, delivery system, fuel availability, climate, terrain, soil type and cost.
I have an extensive background in agriculture and forestry with minors in engineering and chemistry. I grew up on a farm in Iowa where they do dry land farming. In a good year, the rains come at the right time in the right amount to produce good crops. I've seen years when you prayed that it would stop raining and 30 days later, you're praying for rain.
I have experienced flood irrigation in the Salt Lake City area where your choice was water from a canal and you had your designated time to divert water from the canal and that might be 2:00 a.m. I have experienced flood and sprinkler irrigation in the Blackfoot Idaho area. I have experienced every option available in California and I have seen flood and sprinkler irrigation in the countries of Oman and the UAE (United Arab Emirates).
Natural rainfall is ideal if it comes at the right time in the right amounts. Since rainy seasons are of short duration in geographic locations, we have learned to build dams so we can store excess water in reservoirs for future use.
Environmental issues are blocking the construction of new dams. Water rights are becoming a bigger issue every day. Water is becoming our most valuable resource.
The water resources that may be available are: rainfall, rivers, lakes, deep wells, treated waste water, and DriWater
Your delivery system may be one of the following: natural rainfall, rivers, canals, pumping, pipeline and tank truck.
Power/fuel availability may affect your choice of delivery systems, (i.e. electricity, fossil fuel). Climatic conditions will influence your choice of watering options, (i.e., seasonal temperatures, annual rainfall, how much, length of rainy season, length of growing season). The terrain must be considered in your choice of watering options, (i.e. flat land, rolling hills, mountains).
Soil types to be considered are: loam, clay, rocky, sand and gravel.
The overall cost will be the ultimate deciding factor.
The five watering options and their positive and negative points are as follows:
1. Hand Watering - Positive: You can apply water where you want it. Negative: Cost prohibitive.
2. Flood Irrigation - Positive: Low cost, Negative: The most inefficient use of water. Leaches, insecticides, herbicides, etc. into sub-terranean aquifers. Promotes weed growth. Compacts soil.
3. Sprinkler Irrigation - Positive: Installation cost is low, Negative: 85% of water is lost to evaporation and leaching. Leaching same as with flood irrigation but to lessor degree. Promotes weed growth. Compacts soil.
4. Drip Irrigation - Positive Impact: Efficient use of water. Does not leach chemicals. Does not promote weed growth. Does not compact soil. Negative: Cost to install. Maintenance cost.
5. DriWater - 97.5% pure water, 2% vegetable gum, 0.15% alum - Positive: Environmental friendly. Very predictable, releases water over a pre-determined period. Releases water at the roots of the desired plant. Does not promote weed growth. Does not compact soil. Conserves water. Negative: Should not be considered a permanent source of irrigation.
1. Mulching - Loose soil is the best mulch for retaining moisture. Six to eight inches of loose soil will do wonders in retaining sub-surface moisture. Organic mulch will retain moisture and provide the micro environment for many useful organisms.
2. Poly Acrylimide Polymers - Polymers will extend the period between watering cycles. They are only useful if you have the ability to water on a regular schedule. They are not predictable, subject to rapid release of water in hot weather. They may leave toxic residue.
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For information on the outcome of this workshop or integrated weed management in the Pacific Region (Region 1), U.S. Fish and Wildlife Service, Portland, OR, contact: Scott_Stenquist@fws.gov
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