Pauline Knowles, of Wanaka, asks :-

We have a problem with toadstools coming up in our lawn. How can we get rid of them?

Tony Cole, a fungi expert at the University of Canterbury's Department of Plant and Microbial Science, responded.

Providing there is some moisture, you will see many different toadstools popping up on your lawn throughout the year.

The problematic ones are those that form fairy-rings. The toadstools that you see are the visible part of the fungus. However, the main problem is the invisible fungal threads, which grow through the soil in search of nutrients. The fungus both locks up the nutrients which would otherwise be in the soil and also releases toxins.

Toxins are noxious, harmful chemicals. So the grass is starved of nutrients and is damaged by the toxins. Often the grass is killed.

Eradication of the fungus is very difficult. Really the only solution is to remove the soil of your lawn to quitea depth and then remake the lawn with fresh soil whichdoes not contain the fungus. Since it is the fungus that is competing with your grass for nutrients then another approach is to fertilise your lawn to keep the grass well-supplied. In this way you can minimise the effects of the fungus.