Growth and visible responses of Scots pine (Pinus sylvestris L.) seedlings to simulated summer frost

摘要

AbstractScots pine seedlings, 20–30 days old, were exposed to simulated summer frost in controlled environment growth chambers. The responses observed showed extreme variation between individual seedlings; seedlings suffering from needle‐necrosis, healthy‐looking, and dead seedlings were found in the same treatment. Four days exposure to temperatures below –4.5°C caused multiple‐leaders maximally in 7.7 of the pine seedlings and resulted in decreased shoot and root dry weight and sh