Symptoms of Compaction
If you have neglected your lawns aeration then it is likely that it will become compacted and you’re going to see the effects of a poorly aerated lawn as follows:
This is one of the main symptoms of poor air infiltration and compaction in a lawn. A compacted soil holds little air or water and is not going to be able to sustain a normal and healthy population of microbes and beneficial fungi. It is these guys that keep the natural balance of life, death and decay going in your lawn. Without microbes the decay will almost come to a stop. This means that as new grass plants develop and grow the older ones die and just build up in a layer underneath causing a spongy ‘thatch layer’. Once developed beyond a reasonable thickness (1/2”) this thatch layer acts as a barrier to water, air and nutrient penetration further exacerbating the lawns problems. Thatch layers can also occur in patches around the lawn normally in conjunction with localised compaction and or dry patch. See the Scarifying & Raking Category for more detail on thatch
There are other symptoms that a poorly aerated or compacted lawn may exhibit. The problem is that these may have other causes than just lack of air. The fact is a compacted lawn is an unhealthy lawn so an unhealthy lawn, whatever the cause may have similar symptoms.
Worms in the Lawn
More than likely there won’t be any! Worms do some natural lawn aeration so the chances are they gave your lawn up as a bad job a long time a go!
Generally compacted areas have a distressed, dry ‘old’ look to them. Quite often when you add fertiliser they take on a ‘bluey’ tinge due to lack of moisture to assimilate the fertiliser properly.
Though clay soils once dry take a bit of wetting you will find compacted soils cause run-off quite easily
Because of the poor moisture holding capacity of your lawn it will dry more rapidly than other lawns or perhaps neighbouring lawns that are well tended. This may or may not be localised in your lawn in patches often caused by excessive use, dry patch or tree roots.