Delayed Leafing out of Trees

Across the county this spring we have had numerous reports of issues with trees leafing out this spring. There are a couple of reasons this is happening this year. Some of the reports have said the trees started to leaf out, then the leaves turned brown and fell off. The trees then leafed out a couple weeks later. This first issue was most likely caused by frost damage to the fragile new leaves. Most of the time healthy trees will then leaf out again a couple weeks later with secondary buds and be fine.

The second issue we have seen this spring is trees that are not leafing out uniformly across the entire tree or across an entire row of trees. In some cases, the top the tree is leafing out or all the trees in a row have leafed out but one that is just now starting. In this instance there are a couple different reasons this could be happening. One of the first is again frost damage but this damage likely occurred before the leaves started to come out in early spring when we had some very cold nights (lows of 17 and 28) or the sudden drop in temperatures in December that likely damaged those buds. Again, the trees will likely come out of it and be just fine if this is the case.

The second cause for this type of damage is the prolonged drought we have been in. While we have had some moisture recently which has been very helpful, prior to that we had one of the driest, if not the driest springs on record and very little moisture through the fall and winter. The trees are unfortunately stressed out, even trees that have been around for decades or even a hundred years, and this leads to delayed leafing out, thinner leaf canopies and trees that are more prone to insect and disease attacks than normal.

This summer if it continues to be dry the best thing you can do for your trees is to water them at least once a month deeply to help preserve the health of the tree, yes even those that have survived previous droughts. If the tree doesn’t leaf out at all the best way to check if the tree is alive is to scratch the bark off some of the smaller branches with your fingernail. If the tissue underneath is green, the tree may come out, if the tissue is brown that spot is dead.

Have questions? Contact our office where our Horticulture Extension Agent will assist you with questions.

Phone: (316) 321-9660

Email: callae@ksu.edu