Small grains are a brilliant choice for your crop rotation. They offer both a cash profit from harvest and great weed control from broadleaf types, such as clover and plantain. Corn and soybean are popular small grain weed types, but why not take a look at ryegrass, oats and barley? Oats are our particular favourite, being quick to grow and easy to kill, they are also fantastic at weed suppression and erosion control… so what is the problem with small grains?
There’s one major problem with small grain cover crops, so keep reading to find out what that is and more importantly, how to get around it.
Prominent Weeds in Stubble Fields
After you’ve harvested your small grain, or simply cut it down to mulch depending on your cover crop rotation aims, you’re going to find weeds emerging that have somehow managed to avoid your herbicide applications.
In fields of small grain crops such as barley and winter wheat, you’ll find they’re very prone to weeds like waterhemp amongst the stubble after harvest time. This is because they are late emerging and won’t release their seed until later in the season. You might cut down a few weeds during harvest, but the majority of these late emerging weeds won’t start really growing until your small grain is harvested and thus there’s less competition for sunlight, nutrients, space etc.
Now, it may seem like something of little bother, but if you don’t manage these weeds as they emerge there’s a chance they’ll go to seed and really take root in your field, becoming a nuisance that’s hard to remove for seasons to come.
To ensure that your small grain remains a viable crop for your rotation and doesn’t become more hassle than it’s worth, adopt a post-harvest weed management plan using the techniques below.
Post-Harvest Weed Management Plan
Using these techniques, you should be able to get a grip on your small grain harvest. You may even find that you can predict what weeds you’re likely to see in your field stubble – take a look at your soil type, previous weed infestations and the history of the field to work out what you’re most likely to be up against. Knowing in advance will put you far ahead of the game. Use your knowledge to work out when your weeds are likely to emerge and go to seed so you can get one step ahead.
Tiling. This is a great method for removing small weeds that haven’t yet gone to seed, furthermore you’ll also be helping to mulch down your stubble faster and should hopefully improve the soil nutrition and quality. There are downsides to tilling though, especially when you reach the point of over tilling. Furthermore, tilling in weeds that have gone to seed could see them spread even further.
If you have left it a bit later and find that the weeds have gone to seed, it may be worth stepping back for a little while and letting nature take care of the seeds for you. Not only will the small grain stubble be taking up space and protection the soil from coming into contact with the seeds, but the stubble also makes a fantastic environment for seed-eating critters. Think field mice, small birds and other friendly creatures – as they move in to your field they’ll be eating some of the weeds seed and also depositing on the land, thus enriching the soil with manure for free!
If it gets to the point where you need to use strong herbicides to reduce the weeds, perhaps you should re-evaluate your cover crop rotation. There are plenty of other crops you could include to reduce the chances of weeds emerging. Try ryegrass; not only does it grow densely and quickly as a great weed suppressor, but it also fantastic at erosion control and preventing soil from compacting too much, which can be a real problem if you’re tilling regularly to combat weeds.
When picking a herbicide make sure that it fits into your crop rotation and won’t linger to damage the next crop or change soil composition. If you’re unsure on what herbicide to use or how to go about picking a crop rotation, check the label, ask for advice from fellow farmers that might be experiencing the same problems and as always, read more of the helpful articles on our blog!