Trees Adapt to Climate Change by Delaying Leaf Growth

A new study has found that oak trees in temperate forests can delay their spring leaf growth by three days to starve hungry caterpillars. This seemingly small shift in timing disrupted the synchrony between emerging caterpillars and newly opened leaves, reducing subsequent herbivory by about 55%.

The researchers used five years of satellite radar observations across 60 oak-dominated forest sites in southern Germany to track canopy conditions. They found that trees exposed to greater insect herbivory in one year tended to delay their budburst the following spring by around three days.

This strategy works by disrupting the synchrony between insects and the trees they feed on. By delaying the opening of its buds, a tree can increase the chances of newly hatched caterpillars dying before the leaves appear.