PLANTS HELPING PLANTS
Plants living in close proximity commonly make demands on the
same resources. Those that benefit from their neighbors are also
likely to compete with them. Intercropping systems, such as mixtures
of clovers and sycamore seedlings, rely on beneficial competition
between plants. Evidence for beneficial interactions among plants,
however, is relatively scarce but has increased notably within
the last two decades. This article summarizes various ways in
which plants may benefit others growing nearby.
Plants affect the microclimate around them enabling others to
gain growth footholds. Soil modification by one species allows
other species to thrive. Numerous studies have found that diverse
plant communities form 'plant defense guilds' that lower herbivore
loads among themselves. Plants living close together may aid each
other in dispersing seeds and attracting pollinators. The article
also considers the theoretical implications of beneficence in
vegetation, especially as it may interact with competition in
affecting community structure.
A.F. Hunter and L.W Aarssen, BioScience, 1/88, Vol. 38, #1;
pp. 34-40