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Arthur T Knackerbracket has found the following story:

Some trees, such as poplar, have limited resistance to attacks by Asian longhorned beetles, noted lead researcher Charlie Mason, postdoctoral scholar in entomology. In trying to assess the difference in resistance between Chinese poplar and native poplar—which consists of trees secreting compounds into their bark and wood tissues making them unpalatable to the wood-boring beetles—the researchers made a startling discovery: Larval Asian longhorned beetles can consume tree tissues that the adults cannot.

In their study, researchers realized that different plant species had strong effects on adult performance, but these patterns did not extend to effects on juveniles consuming the same hosts. They saw that female adult beetles were capable of producing eggs when feeding on red maple, but not when provided eastern cottonwood, also called necklace poplar, or Chinese white poplar.

Yet females that produced eggs by feeding on red maple deposited eggs into all three plant species and the larvae that hatched from these eggs performed equally on the three hosts. The differences between adult and juvenile utilization of poplar was very different.

"That is because poplar has markedly higher salicinoid phenolic concentrations in bark, which discourage adult Asian longhorned beetles from feeding, while poplar wood had only trace amounts," said Mason. "The tree's resistance is due to compounds present in the bark that make it unpalatable for adults."

But the adult female cuts a small notch in the bark and deposits her eggs, and the hatched larvae from there are able to tunnel into the wood tissues and be nourished by eating them, avoiding having to feed on bark.

By feeding on the wood and burrowing through tree limbs, making them weak, unstable and liable at any time to collapse on people below, Asian longhorned beetle have wreaked havoc on trees in urban areas such as New York City, Worcester, Massachusetts, and Chicago. The damage they caused has resulted in the removal of thousands of infested trees.

Divergent host plant utilization by adults and offspring is related to intra‐plant variation in chemical defences^[$], Journal of Animal Ecology (DOI: 10.1111/1365-2656.13063)

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