Seasonal Needle Drop
Every year, evergreens experience a seasonal needle drop that is a normal part of the plant's cycle. Needles of conifers have varying life spans and do not remain attached indefinitely to the tree. Many evergreen needles, as they age, will turn yellow, then brown, and drop off after one to several years. The change can be gradual, or, with some species, quite rapid. Seasonal needle drop can cause concern to homeowners who are not familiar with this natural occurrence. In times of drought, needle browning may be particularly noticeable, because more needles are shed in response to environmental stress. White pines show the most dramatic needle drop change. Their annual loss of needles can be especially alarming on mature white pines, as the number of yellow needles outnumbers the current season’s green growth. Typically, white pines will retain needles for three years, but in autumn, 2-or-3-year-old needles will change color and drop, leaving only the current season’s growth still attached. Austrian and Scots pines usually retain their needles for three years. Red pine drops its needles in the fourth year. Spruce and fir needles also turn yellow and drop, but the change is usually less noticeable because their older needles are thinned progressively, making the process more gradual than in pines. Arborvitae sheds branchlets rather than needles which usually turn brown as they age, yet remain on the tree for quite some time before falling. Yew needles turn yellow and drop in late spring or early summer of their third year. Check your plants regularly. If the current season’s growth is discolored or wilted, the tree may be suffering from a more serious disease or insect problem and should be diagnosed to determine if control is warranted.
|Seasonal needle drop on arborvitae||
Seasonal needle drop on pine
There is no control required. As long as needle drop is restricted to older growth and is not excessive, the “problem” is simply seasonal needle drop, a normal and natural process. Always follow good cultural practices to keep trees healthy.
- Large Evergreen Trees (over 20 feet) 33%
These trees can reach heights of 80 feet, and most hold their needles year-round, providing seasonal color in winter. Many are dense, offering a screen or privacy, and windbreak. Besides green, evergreens can be silver-blue, blue-green, and...
- Low-Growing Evergreen Shrubs 32%
The fine-textured foliage and formal silhouette of Buxus 'Glencoe', Chicagoland Green™ boxwood, offers an important year-round structural element to any landscape Generally grow less than 4 feet tall Include cone-bearing plants with...
- Pruning Evergreens 31%
Evergreen refers to a group of plants that retain their foliage during winter. Most evergreens have a strong central branch leader, which requires little pruning except to control plant height, increase the density of branching, or to shear into...
- Intermediate Sized Evergreens (6-20 feet) 30%
Growing 6-20 feet tall, they retain foliage year-round, and soften structural edges around foundations, under windows, at corners, or against walls. Like mid-sized shrubs, they create structure and depth in mixed plantings, and provide backdrop for...
- Low Growing Evergreens (generally less than 6 feet) 30%
Generally growing less than 6 feet, these shrubs screen unwanted objects and views all year, can be used to stabilize slopes or embankments, and add color to winter landscapes. They come in a variety of shapes and sizes, from mounded to upright to...
- May 1, 2009 Plant Health Care Report 22%
This issue contains details on many items including: Caterpillars and sawfly larvae Eastern tent caterpillar European pine sawfly Arborvitae leafminer Oystershell scale Apple scab Cryptodiaporthe canker (golden canker) Seasonal needle drop...