Monday, August 14, 2006

Colonisers and succession
Colonisers are plants which move into sites which have been recently disturbed eg bulldozing, and start the process of getting a climax community going. For instance gorse is a coloniser which if i remember correctly moves in after fire, it makes nitrogen available (a vital nutrient) and creates suitable conditions for New Zealand natives to grow. Gorse is such a good colonizer it is now being planted by the waitakere city council.
Colonisers reproduce quickly and often spread by asexual means eg runners. We tend to think of colonisers as "weeds" but this is only because our methods of food production tend to leave the soil exposed and tend to disturb the soil regularly. Many sustainable horticultural systems use these weeds to establish perrenial food production systems eg permaculture and food forests both of which i will blog on in future.

This is a wattle tree growing across the road from me on the land i am guerrilla gardening on, its a few months old and is making nitrogen available from the air and breaking up the soil.
This is a mixed species early succession site in new market with fennel and various grasses and shrubs growing over a rocky slope. If left alone this would eventually become a mixed species forest. Early succession such as this can harbour great diversity and provide a habitat for many beneficial plants and insects. This is blackberry growing at unitec it provides a food source and moves into recently disturbed sites especially those that have been burned off i think.

All photos taken today

1 comment:

Anonymous said...

Interesting.

This topic would make a good article for a students' magazine.

I remember years ago seeing in a book, a diagram of before and after fire growth. It showed different types of plants becoming established after the fire than what was there previously.

Would native trees be quicker to establish than exotic trees say Pinus Radiata?