There have been a number of letters to the editor in recent weeks which express concern regarding the application of pesticides in Prince Edward Island, including pesticide use by P.E.I. potato growers. I would like to take this opportunity to try and dispel some of the myths relating to agricultural pesticides as well as to ensure that Islanders have accurate information on how pesticides are responsibly used. Pesticides are generally defined as a natural or synthetic product used to control fungal diseases (fungicide), insects (insecticide), or weeds (herbicide).
Readers have no doubt seen large agricultural sprayers in Island fields or on the highways. Many of these sprayers hold up to 4,000 litres of water, enough to spray 40 acres of land, or the equivalent of 30 football fields. At first glance, that may appear to be a lot of pesticides going on fields; however, it is important to note that for a routine fungicide application (the most common pesticide used on P.E.I.), less than 1 kg of actual pesticide is applied to each acre of land, diluted in a large tank of water. This is roughly equivalent to spreading a 1 kg bag of sugar over an entire football field. For most herbicides and insecticides, the levels of active ingredient per application are much lower, with some products being measured in grams per acre.
The majority of pesticides used on Prince Edward Island potato fields are contact fungicides which protect potato plants from contracting late blight, the same potato disease that caused the Irish potato famine in the 19th century and led to many of our ancestors to immigrate to Canada. Potatoes grown in wetter climates like P.E.I. are susceptible to infection by the fungus causing late blight, so all commercially-grown potatoes in P.E.I. (both conventional and organic) use protectant fungicides to prevent infection. There is no cure once a plant is infected, so if potato growers did nothing to address late blight, our potatoes would rot in the field or in storage and our province would not have a potato industry. Additionally, it is important to add that these contact fungicides are not absorbed by the plant itself and do not make contact with the potato tubers growing under the ground.
Farmers are very careful with their use of pesticides and only apply them when necessary. Most farmers practice what is called integrated pest management (IPM). This means they make use of a variety of preventative practices to avoid pest issues and when pest problems arise they make use of all available pest management tools, including mechanical, biological and cultural controls as well as pesticides. As well, crop scouting is routinely used by the majority of farmers to determine whether pest levels warrant application of control methods.
Island potato growers don’t spray pesticides simply out of habit. Pesticides are a major expense in potato production and reducing the amount of pesticides required to grow a crop of potatoes is a goal of everyone in the industry.
Nonetheless, using pesticides to control diverse pests such as late blight, wireworm, and Colorado potato beetle is necessary to grow high quality potatoes for consumers.
Advances are being made continuously to make pesticides more targeted in effectiveness while reducing impacts on the environment and on humans. The broad-spectrum pesticides of yesteryear have largely been discontinued, with pesticides of today being designed to target only the pests that are impacting the crop.
In addition, many potato growers are embracing new technologies such as GPS and band spraying to ensure that only the required amount of pesticides are being applied only in the right place. All agricultural pesticide applicators in Prince Edward Island must be licensed by the province after receiving training on the proper use and handling of pesticides and passing a subsequent exam. These licenses must be renewed every five years.
The potato industry makes up almost half of the agricultural cash receipts each year and is worth over $1 billion to the Island economy annually. Regulated and safe application of pesticides, which have be reviewed and approved by Health Canada, is an integral tool in producing only the best quality potatoes for Islanders as well as our customers around the world.
Gary Linkletter is chairman of the Prince Edward Island Potato Board and is a potato grower in Linkletter