Ian McLean Spokesperson for the Green Party

It is prickle season again, with Onehunga weed (Soliva sessilis) invading our parks and gardens.

There are sprays to control it, but those sprays (pyridine herbicides) are persistent in soil and compost heaps, and can attack vegetables, flowers and trees. They also have health effects for people despite assurances otherwise.

Here are some alternatives.

Mow the grass less often. Soliva doesn't like being shaded. Dampness also keeps the prickles soft, which is why there were few prickles in the so-called summer of 2011-12. You can't water the lawn every day, but letting it grow longer retains moisture and benefits birds.

Tolerance: children wearing shoes ignore prickles. Of course, dogs don't wear shoes and children lie on the grass. However, the prickles are finished by mid-January. There is still lots of summer with no prickles.

Try less lawn! Have more vegetables and flowers. Your children will eventually thank you for their herbicide-free world.