I have been out scouting a lot of fields this week and we are seeing a lot of weeds in some of these fields. This is the perfect time to scout your fields for weeds. Weeds will green up first before your previously planted perennials. If you’re going to establish a spring planted perennial plot, here is some strategies.
So many people want to get out and spray roundup in your plots before planting and this is a good strategy but there is the correct timing of spraying and the correct rates. Let’s first discuss how glyphosate (Roundup) works. Once absorbed into the leaves, glyphosate cannot be broken down. The glyphosate moves quickly through the plant and accumulates in areas of active growth called meristems. Spraying a plant with Glyphosate (Roundup) results in a lack of protein synthesis in that plant. Without amino acids, Plants stop growing. The key thing to note here is actively growing plants. If temperatures are cool, the weeds and plants your trying to kill are dormant or in shutdown mode. The result will be poor kill. Another time you shouldn’t spray herbicides is when temperatures are extremely hot. During excessive heat, plants also are on shutdown mode. The result again will be poor kill.
Temperatures should be at a minimum of 60 degrees and with a few days of active growth. You also should monitor the weather forecasts as you need 3-4 hours for the chemical to be on the weeds before a rain. Some versions of glyphosate are more rain fast then others.
Application rates: The labels state a minimum of 1 quart per acre of most common 41% solution glyphosate products. The prices of glyphosate have really dropped over the years and there is no reason to skimp on product. With so many weeds becoming roundup resistance, let’s do our part to not stunt weeds but kill them. Stunting weeds is a fast way to make your weeds roundup resistant. So, my recommendation is to use 1.5 to 2 quarts per acre of glyphosate. Many grasses and broadleaves require a higher level for effective kill. I also ask people if they use ammonium sulfate with their roundup. Very few of you are doing that. It clearly states on the labels about this. You can either use dry ammonium sulfate or liquid. You between 8.5 and 17 lbs. of dry ammonium sulfate per 100 gallons of water. The liquid form of AMS typically is 2.5 to 5 gallons per 100 gallons of water. This is especially beneficial for those of you who have hard water.