Throughout the last 40 years, the trend has been to replace pesticides with pest control provided by the plant, either through genetic engineering (transgenic plants) or through traditional plant breeding. Examples of genetically engineered crops are Bt and glyphosate-resistant corn hybrids and glyphosate-resistant alfalfa varieties, while improved disease resistance in corn and alfalfa plus leafhopper-resistant alfalfa are a result of traditional plant breeding efforts.
The seed of genetically engineered crops costs more, while varieties with improved disease resistance and leafhopper-resistant alfalfa seed don’t usually have a price premium. The result is that fewer pesticides are used in the control of leafhoppers, corn rootworms and European corn borers, as farmers have traded jugs for genes. Even so, unless a farmer uses a custom pesticide applicator, there will probably be a few full or partly used containers of pesticides on hand after the growing season is over. Proper storage of these pesticides is important not only from a safety standpoint, but also so the products will be usable next year.
Read the label (again!)
You should always read the label before using any pesticide, and if it’s a liquid formulation you should also read it before it goes into winter storage. Few pesticides are now sold in glass containers, but this wasn’t always the case, and some of these products were highly toxic. Worst case, a pesticide can freeze and break its glass container, resulting in a hazardous mess. The label will state if the product can be frozen, or at what minimum temperature it can be stored. Some labels simply state “prevent from freezing,” while other pesticides shouldn’t be stored at temperatures below 40 degrees Fahrenheit. Pesticides can be stored in a heated building that’s used as a shop, but should be in a separate storage area or cabinet.
At Miner Institute, liquid pesticides are stored (under lock and key) in an insulated and heated space walled off from the unheated seed storage area. A small space heater with a thermostat is set for about 50 degrees Fahrenheit, and it doesn’t take much electricity each year to heat this storage area. Granular pesticides, including water-dispersible herbicides and granular insecticides, may not need to be kept from freezing, but should still be stored “high and dry” in a secure storage area or cabinet.
If you did your best storing chemicals, but next spring realize that a liquid pesticide that was supposed to be stored above freezing was exposed to freezing temperatures do you toss it? No. Always adhere to proper disposal of pesticides, but first check the label, as some include information on testing a previously frozen product to determine if it’s still usable. Often the recommendation is to add a small amount of the product to a quart of water to see if it readily goes into solution with no remaining residue on the bottom of the container, but read and follow the instructions for testing on the label of your particular product. Pesticide labels also include contact information for the manufacturer, another good source of information.
Storing farm seeds
It’s unusual that a farm doesn’t have some seed left over from spring planting. Whole bags of seed can often be returned for credit to the dealer, but once a bag of seed is opened you own it. Most farm seeds will store well for a year or more, and whatever seed you didn’t use in 2014 should still be viable this coming spring. Seeds should be kept cool—below 50 degrees Fahrenheit—and freezing is fine. At Miner Institute, we store leftover seeds in the freezer and have never had a problem when using seed that was stored this way.
Seed corn stores somewhat better than some other species, as we discovered many years ago when Miner Institute acquired two bags of seed corn that were several years old. Although we were skeptical about the seed, we performed a germination test on a sample from each bag. Much to my surprise, the germination on both bags were more than 90 percent, not much lower than the germination percentage stated on the seed tag.
You don’t have to send seed away to have it germination tested. Here’s a simple test you can do at home next spring: Take 10 seeds and space them evenly on a damp paper towel. Roll up the paper towel and put it in a plastic food storage bag. Leave it in your kitchen or another warm place for several days, and then check to see how many seeds have germinated.
Lighting conditions won’t affect the results. If by the end of a week eight of the 10 seeds germinated, there’s a good chance that germination of the entire lot will be about 80 percent. Compare this to the seed tag to see what the original germination percentage was when it was tested by the seed company. I wouldn’t recommend using seed that’s lost a lot of viability, but expect in most cases you’ll find that any seed that you’ve held over for a year will still be good.
I’d be particularly careful to test leftover reed canary grass seed, since there are reports that this species doesn’t store well. Although I have no personal experience with this, I’ve also heard that some seed corn coatings may affect the storage life of the seed. If in doubt, check with your seed supplier, since he may have more information on this.
Most forage legume seed, such as alfalfa and clover, is pre-inoculated by the seed company. An inoculant is living bacteria and, therefore, is sensitive to heat and moisture. Look on the seed tag to determine the expiration date of the inoculant; if the seed was stored in unusually warm conditions, the inoculant might be dead long before the expiration date. Don’t take chances: A package of bacterial inoculant is cheap compared to the cost of a bag of legume seed. If you purchase fresh inoculant make sure the inoculant is matched to the crop species—with bacterial inoculants, one size does not fit all.