February 1, 2019
Letters to the Editor Febuary 2019
Brent Ayles’s article entitled “The hard way” (November 2018 Landscape Trades) was excellent.
People spend a lot of money on self-help books, videos and seminars in the hopes of getting direction. This writer has done this in a one-page article.
His straightforward advice is applicable to a wide range of readers. I commend him for this most refreshing approach.
Everett Construction and Landscaping
Editor’s note: The following is an anonymous reader survey comment; we are publishing it as a letter to invite responses.
The landscape industry can make one simple change that will have a significant impact on sustainability — improve soil moisture-holding capacity by installing additional and better quality soil. By example, in 2018 in the Oakville area of the GTA, a landscape with four inches of soil required 30 irrigation events all season (based on actual ET and rainfall data for 2018 and a Managed Allowed Depletion level of 50 per cent). If there was six inches of soil installed on the same landscape, only 18 irrigation events would have been required (these frequencies are based on a sandy/clay/loam soil). To the irrigation industry, stop wasting water by setting simple timers to arbitrarily water the landscape based on a day-of-the-week schedule. Watering three times per week in Oakville in 2018 resulted in at least 70 irrigation events, more than double what was actually required.
Also, do independent research on “Smart Irrigation Controllers.” The vast majority do not work because of poor quality and insufficient ET data or rainfall measurement. Many have proven to increase water consumption over and above the arbitrary timer settings. Education, research, and simple performance measurement are simple ways to avoid blind belief in the marketing hype. Flow monitoring is becoming very inexpensive to implement and many municipalities are investing in dedicated irrigation meters making measurement a very simple process. As they say, “the proof is always in the pudding.”
Damage caused by over-watering includes:
Nutrient leaching causing pollution of our river systems. This leads to additional, unnecessary, fertilizer application which is then leached out again by over-watering (a vicious cycle of events). In areas with a clay sub-soil (poor drainage), more trees and plants die on irrigated landscapes from drowning than from a lack of water.
Water waste from irrigation is lost for downstream use. Unlike domestic waste which is virtually recirculated back to the source, water waste from irrigation is a net draw from the river system and is no longer available for downstream use.
Unnecessary water expenditures and water treatment. Canada has some of the highest water-use rates in North America. Savings are a win for everyone. For example in 2018, Ikea Calgary saved over 6.6 million litres of water, or over $17,000 in water costs, through an effective, automated, commercially available irrigation water management system.
The environmental focus is currently on CO2 but water is likely going to be a much larger issue in the decades to come. With water and irrigation, it is not the use of water that is the primary problem, it is the extreme waste and subsequent pollution that is the larger problem. Healthy plants reduce CO2 and produce oxygen. Unhealthy, dying, and dead plants produce more CO2.