Pre-harvest Herbicide | Parrish and Heimbecker, Limited

Simplify your harvest

with pre-harvest products

Find the right product for your Pre-Harvest Application

As we get closer to harvest, there are a number of factors to consider to make your harvest easier, and to ensure your crop is marketable. P&H can walk you through these decisions and help you select the right strategy for your farm.

The benefits of pre-harvest.

There are two primary reasons to apply a pre-harvest herbicide. The first is for weed control.  Hard-to-control perennials such as Canada Thistle and Quackgrass are best controlled during the fall when leaf area is at is maximum. This is the primary reason pre-harvest should be considered in crops such as cereals with crop staging being critical.

For wheat, preharvest application can only occur when the crop is at 30% or less moisture content. This is usually three to five days before you would normally swath. At this stage, if you press the kernel with your nail it will leave a dent in it.

For complete details on preharvest use in wheat and other crops, see the Keep it Clean link below.

The second reason to apply pre-harvest herbicide is for crop dry down.  Certain pre-harvest products like diquat and Heat will help dry out the plant and accelerate the overall maturity and harvesting process. It can also help mitigate uneven crop growth and control weeds. It’s important to note that glyphosate is not to be used for desiccating purposes.  Not only is it ineffective, (takes over two weeks to dry down) but it gets absorbed by an immature crop which leads to residues in the grain.


Summary of where pre-harvest products are allowed.

  Glyphosate Heat LQ Diquat
Canola Yes Yes Yes
Wheat Yes Yes No
Barley Yes Malt – Consult with
grain companyFeed – Yes
No
Oats Consult with
grain company
No No
Peas Yes Yes Yes
Soybeans Yes Yes Yes
Chickpeas Yes
(WeatherMax, Transorb)
Yes Yes
Potatoes No No Yes
Flax Yes No Yes
Lentils Yes Yes
(Red lentils only)
Yes
Fababeans Yes No Yes
Dry bean Yes Yes Yes
Cereal Seed Crops No No No


Talk to your Grain Buyer

When considering pre-harvest products like glyphosate, Heat or diquat, it is important to pinpoint what exactly you are trying to accomplish, and in which crops.  It is very important to check the declarations of grain buyers to see if they will accept grain treated with certain products. P&H will work with you through these considerations and help you pick a product that will meet your operation’s needs.

Visit your local P&H retailer to learn more about pre-harvest products and the considerations you should make when using them. Our team of experts is ready to help.

For complete details on pre-harvest products by crop, visit Keep it Clean.