Birch dieback is usually caused by a lack of water. In their native habitat, birch grow in moist locations, usually near lakes and streams - conditions not found in most yards.
Sparse foliage and dead branches at the tops of birch trees are a common sight. The first sign of damage usually starts in midsummer with the leaves turning yellow and dropping off. Dieback generally begins towards the top of the tree and at the ends of the branches. The following spring, some branches may be dead and the tree will have sparse, unhealthy looking foliage. Under severe drought conditions, the tree may die or become infested with insects such as the bronze birch borer. Trees under moisture stress are also more susceptible to winter injury.
Adequate amounts of water are necessary to keep birch trees healthy and prevent dieback. Watering the lawn may not be enough because the grass may use most of the moisture. It is important to water the tree separately from the lawn to make sure it receives enough water. If there is no rain, the tree should be watered every two weeks during the summer. The soil should be soaked to at least 20 cm (8 inches), but 45-60 cm (18-24 inches) is preferable. The amount of water required to soak the soil to these depths will depend on the soil type. The area to be watered is halfway from the trunk to the drip line and the same distance beyond the drip line. The drip line is an imaginary line on the ground directly beneath the outermost tips of the tree's branches. It is more important to water this area rather than next to the trunk. It is advisable to reduce the amount of water in late August and September to allow the tree to harden off. In early to late October, trees should be watered well in preparation for winter.
If grass does not surround the tree, it is important to mulch the area to prevent moisture loss. Landscape fabric may be used to cover the soil to prevent weed growth. Mulches including pine cones, bark chips or decorative rock are useful for shading the soil and conserving moisture.
Should your birch be experiencing dieback, please contact us