Wednesday, April 22, 2015

Fruit tree freeze deaths

Subzero temperatures the second week in November did more damage than just preventing normal leaf drop (see Jan 16 "2014 Gardening Year in Review" post). As normal times for Front Range fruit trees to leaf out have come and gone, realization is dawning among home fruit growers that parts and indeed whole trees are dead. A warm fall did not allow trees to fully enter dormancy leaving them unprepared for the sudden, early subzero temperatures.

The row of sour cherries pictured have only a scattered bud or two alive. These few green buds will likely shrivel when summer heat arrives. Already gummy sap is oozing as a stress sign confusing some that peach tree borer is responsible despite the location higher in the tree than the soil line (no frass present either). See CSU Extension's fact sheet for information about Peach Tree Borer.

Few apple branches
 flowering/leafing on this tree

Not only cherry but in some cases generally hardier plum and apple trees show damage. In addition to fruit trees, damage of landscape shrubs and trees will become noticed more as the season progresses. Notable casualties to date include burning bush and spreading ('Manhattan') euonymus, rose, pyracantha, boxwood, privet, weigela, hibiscus, smoke bush, spiraea and buckthorn.