Weeds on Sports Pitches Guide, is just that a basic guide one Groundsman/Greenkeeper to another. Where do weeds come from, how do we control them and do weeds tells us something about the soil itself?
I have left out the Latin names, as really who uses them on a day to day basis.
What are weeds and why are they an issue?
Weeds get a bad press; one mans weed is another’s wild flower and a weed is really just a plant in the wrong place.
A few weeds are not the end of the world and only a problem for the perfectionist amongst us, but if there are a lot of weeds in numbers, they are competing with the grass plant for nutrients and water.
Not only do they look out of place, but on finer turfed sports surfaces they can affect ball roll and or create bare areas during preparation, so the higher the level of surface quality required more weeds become an issue.
Weeds can also be a sign of a lack of nutrient, compaction and other deficiencies.
What types of weeds are there?
There are too many to speak off, but l am just going to focus on a few of the most common found on sports pitches. These are, Daisy, Dandelion, Clover, Plantains, Yarrow, Speedwell and buttercup.
Where do weeds come from?
Weeds come from many sources including, air borne weed seeds, bird poo, unsterilised topdressing, transported by foot/machine.
Where do we get weeds?
Weeds like, moss weed grasses are just looking for a bare area to take over, these can be in the form of old divots not fully grassed back, worm cast, areas where moss has died back or basically any bare areas.
What can weeds tell us about the soil?
Clover can be a sign of a lack of soil nutrition, specifically nitrogen.
Plantains, are said to be indictors of a compacted soil profile and possibly why they can be seen down the middle of some winter sports pitches, although the bare surface has to be factored in. Plantains can also be a sign of low fertility in the soil, maybe backed up by the volume you see on council football pitches, that don’t get fed.
Dandelions (so called king of weeds) are another sign of compaction.
How do we control them and when ?
Culturally removing is generally more of a option for less established tap rooted/bulbous rooted weeds. However shallow rooted weeds such as daisies and plantains are very easy to remove via a gentle easing and lifting with a knife.
Tap rooted weeds, these are a major challenge to remove due to the depth of the roots i.e., Dandelion.
Shallow rooted, can be removed by gently pulling out with root intact- Daisy, Plantains.
Bulbous roots- Clover, Buttercup, Speedwell.
As a last result is an application of a selective herbicide, this is usually needed when there are too many weeds to control culturally and or they are well established tap/bulbous roots.
Applications of herbicide are best made, prior to an application of fertiliser, this helps the grass fill in around the dead/dying weeds. I have also noted that it is best to apply an herbicide in early summer, when the grass plant isn’t too stressed and the grass and weed is actively growing.
There is always an option to spot weed, rather than apply a blanket selective application.
Look at your seed rates, weeds are invasive and opportunist if we can provide a thickly grassed surface there will be little or no room for weeds.
Manage worm casts, as best you can by disperse and diluting down where and when possible.
Encourage a thicker grassed surface, with a regular programme of cutting, verticutting and feeding.
Reduce compaction, as some weeds are an indicator of a compacted soil.
If you /me need three takeaways from this it is that weeds will flourish, where bare soil (seed rates key) is apparent, under fertilised and compacted.
That’s my experience, what is yours please leave comments below!
Brian on behalf of the TurfCareBlog community.
Images kindly given by Tom Wareham Grinstead of Sussex Cricket, where he is a Groundsman.
Talking of weeds, take a look at a recent blog on weed grass, more commonly known as Poa – https://turfcareblog.com/annual-meadow-grass-on-sports-grounds/