Before You Buy - Comparing Pesticides

Fabian Menalled

Reports of pesticide products being sold over the phone to farmers is a spring time ritual in Montana.  Now that some commonly used pesticides are no longer patented, these products are being manufactured and marketed by many companies.  Some of these companies often make wild claims to the effectiveness of their products.  These products may appear cheaper than name brand pesticides, but they carry a hefty price, particularly when you consider that the product itself may contain a very low dosage of the active ingredient.

The best way not to fall victim to one of these scams is to ask for a label before any purchase.  The label contains useful information on how the pesticide comes packaged (the formulation), the percentage of active ingredient (the ingredient that actually kills the pest), the percentage inert ingredients in the formulation (basically fillers that have no pest control qualities), use rates, and EPA registration numbers.

With the label in hand you can then check the formulation ingredients and compare it to an original product.

Here are some typical concentrations of herbicides formulations that you can compare with those sold over the phone:

• 2,4-D ester - 4, 5, or 6 lb active ingredient (a.i.)per gallon. An a.i. of 70-80%  is considered a good buy. Some herbicides sold over the phone are a 10th of this concentration. Note: if this herbicide is part of a mixture the percentage of active ingredient may be lower.
• 2,4-D amine - 4 lb. active ingredient (a.i.) per gallon. Typical percent of a.i. is about 40-50%
• MCPA  ester - 4 lb. active ingredient (a.i.) per gallon. An a.i. of greater than 60% is considered a good buy.
• MCPA amine -  4 lb. active ingredient (a.i.) per gallon. Typical percent of a.i. is about 40-50%.
• 2,4-DB - 2 or 4 lb. active ingredient (a.i.) per gallon. An active ingredient of 20-30% is typical.
• glyphosate (Roundup®) - 4 lb active ingredient (a.i.) per gallon or 3 lb. acid equivalent (a.e) per gallon. Greater than 40% active ingredient (a.i.) is typical
• dicamba (Banvel®) - 2 or 4 lb. acid equivalent (a.e.) per gallon. Active ingredient can range from 30-50% a.i. for 4 lb. per gallon material (Clarity, Banvel,) and 20-30% for 2 lb. per gallon material (Banvel SGF). Some dry formulations of dicamba may become available-just be aware that the acid equivalent (a.e) rates for dicamba in small grain is 1-2 oz/a and in corn and grass is 4-8 oz/a)
• bromoxynil (Buctril®) - 2 or 4 lb. (new formulation) active ingredient (a.i.) per gallon (34% active ingredient (a.i.) per gallon
• bromoxynil + MCPA ester (Bronate®) 2 + 2 lb active ingredient (a.i.) per gallon (32 and 34% active ingredient (a.i.) respectively)
• trifluralin (Treflan®) Liquid formulations are usually 2 or 4 lb active ingredient (a.i.) per gallon with 31 to 43% active ingredient being typical. Dry formulations are 5-10% by weight (5-10% active ingredient (a.i.).
• ethalfluralin (Sonalan®) Liquid formulations are usually 2 or 4 lb active ingredient (a.i.) per gallon with  31% active ingredient being typical. Dry formulations are 5 to10% by weight with 10% active ingredient (a.i.) being typical.

Once you have a label of the product being solicited and some information on other formulations of the same pesticide active ingredient (a.i.), you can then calculate the rate based on formulation and also calculate the cost per acre based on per unit volume cost and rate per acre.

Here are some other tips for dealing with pesticide tele-marketers: 

• Pesticides sold through the mail or over the telephone are often unregistered and cannot legally be sold in Montana. All pesticide products used in Montana are required to be registered with both the Environmental Protection Agency (EPA) and the Montana Department of Agriculture.
• Purchase products only from a local dealer with an established business location. Avoid vendors whose only address is a post office box.
• Be sure to examine the pesticide label to ensure that it is labeled for the intended use. Most local dealers have a supply of specimen labels for the herbicides they sell. Demand that the solicitor provide the EPA Registration Number of the product and an advance copy of the label before agreeing to accept shipment of the product.
• Telephone solicitors often misrepresent the products they sell, either recommending them for inappropriate uses or exaggerating the length of their residual activity.
• Avoid vendors who claim they can provide a product "just like" one of the best-selling herbicides for on-third to half the price of the best-seller. There is no free lunch! If a deal sounds too good to be true, it probably is!
• When ordering anything by mail or telephone, the best way to pay for a purchase is by credit card. Under the fair credit billing statutes, you have the right to withhold payment for products that are unsatisfactory or misrepresented. Most credit card companies are quite willing to assist consumers in resolving such disputes with vendors.

Acid Equivalent (a.e.) - The theoretical yield of the original parent acid from the active ingredient content of a formulation. Some acid-based pesticide molecules are sometimes altered to form either an ester or a salt. This helps a pesticide become more water soluble or impart other beneficial characteristics to a pesticide other than its pesticidal effects. So, some salt and ester formulations are expressed as both active ingredient (with the salt or ester component) and as acid equivalent (the yield of the original acid molecule). For example, the active ingredient for certain glyphosate formulations is 4 pounds per gallon while the acid equivalent for the same formulation is 3 pounds per gallon.

Active Ingredient (a.i.) - The unaltered chemical in a pesticide formulation that is primarily responsible for its pesticidal effect

Categories: Weed, Acid Equivalent, Active Ingredient, Herbicide Label

Date: 04/14/2005