Category Archives: Abiotic

May 23, 2019

Winter Injury Spring 2019

Symptoms of winter injury have been showing up on conifers over the past month.
In upstate NY sub-zero F temperatures were recorded in late January and in early March we experienced a sudden drop of temperatures from above freezing to the single digits in one day.   These low temperatures and fluctuation events are likely the cause of the winter injury symptoms we are seeing now.
Individual plants in grand fir plantings were affected, sometimes with the entire individual trees dying back.

Conolor fir (foreground) and Grand fir (back left) displaying winter injury.

Concolor fir (foreground) and Grand fir (back left) displaying winter injury.

Junipers and spruce were also affected in some areas.

Juniper with a major portion of the shrub showing dieback.

Juniper with a major portion of the shrub showing dieback.

We also are observing some needle desiccation on younger trees.

Young fir trees with brown symptoms winter injury.

Young fir tree with winter needle desiccation.

April 13, 2015

Winter Injury 2015

Many growers were looking at winter injury at this time last year.  This winter the cold weather was even more severe across NY and the Northeast.  So unfortunately much of what we mentioned last year is true again.

Grand fir 2015

Grand fir trees with winter Injury. More severe damage above the snow line.

Grand fir needles

Needle browning due to low temps on Grand fir.

Varing degrees of Injury on concolor fir

Varying levels of winter injury on a field of concolor fir.

Nordmann fir with winter Injury.

Nordman Fir with winter injury

Although most of the affected trees will survive with the buds and new growth unaffected, this occurrence, two years in a row now, has some growers questioning whether they’ll put in more of these tender species.

July 8, 2014

Tree Diversity Minimizes Pest Problems

A diverse Christmas tree planting.

A diverse Christmas tree planting in Upstate New York.

A large planting of a single species is easier to manage and harvest but can be a windfall for pests. Monocultures allow insects and disease to expand rapidly as the pest can move unimpeded from one plant to another. After the devastation that occurred in community forests with streets lined exclusively with American Chestnuts (Chestnut Blight) and American Elms (Dutch Elm Disease), planting a diversified mixture of trees is now the standard practice among municipalities.

Dead Fraser fir with healthy Canaan Fir foreground and turkish fir behind. side.

Dead Fraser fir with healthy Canaan Fir foreground and Turkish fir behind.

Many nursery and Christmas tree growers also know the advantages of growing a variety of species.   They’ll choose tree species to fit their different environments on their farm.  Then just like the smart investor who has diverse portfolio to minimize risks in the future, diverse plantings can prevent pests from moving in and wiping out all the trees.  Even landscape designers when working with customers who envision a planting of a single species will often try to specify a mixture of similar species to increase resilience.

There's increased interest in Turkish firs such as this example of Abies bornmuelleriana because of it's root rot resistance.

There’s increased interest in Turkish firs such as this example of Abies bornmuelleriana because of it’s root rot resistance.

Having a diverse planting works because most insects and diseases have preferences for the host species they feed upon.  Many simply cannot live on a different genus, for example it is rare to find an insect or disease that lives on both fir and spruce trees.  In addition certain sites on a farm or landscape may be more conducive to one species over another.   For example if  a species is mis-matched on a site with soil conditions it cannot tolerate, then the whole planting may succumb to a root rot.

Growers taking notes on new tree species they may want to add to their plantings at Cornell Plantations.

Growers taking notes on new tree species they may want to add to their plantings while at Cornell Plantations.

Cornell Plantations is one place where you can experience and compare a wide variety of deciduous trees and conifers.   Although their plantings extend over several acres on campus, a concentration of conifers can be found at the Kienzle Overlook. http://www.cornellplantations.org/our-gardens/botanical/kienzle-overlook .  At this website you can find a list of the 80 + conifers species that are in that planting.

Phil Syphrit

Phil Syphrit

Phil Syphrit pms26@cornell.edu is the curator of this collection and can help answer questions on some of these unusual conifers if you are interested in adding them to your plantings.

May 7, 2014

Winter Injury

 

What a winter!  It was long and cold.  We experienced a couple of polar vortex events and subzero Fahrenheit temperatures were common.

WInter Injury visible on the Nordmann fir trees in the foreground.

Winter injury symptoms of needle browning visible in the foreground on Nordmann fir trees.

Evergreen trees and conifers were impacted by the extreme conditions. The symptoms of the winter injury has been showing up on evergreen needles for the last month or so.  The damage is appearing as needle browning– sometimes whole needles and sometimes just the tips.

Some of the species affected this spring :

Winter Injury symptoms is common Nordmann firs.

Winter Injury symptoms is common Nordmann firs.

Grand fir trees are showing winter injury symptoms in many parts of NY.

Grand fir trees are also showing winter injury symptoms in many parts of NY.

 

 

 

 

 

 

Douglas fir trees that have swiss needlecast infections were most prone to winter injury. Some un-treated landscape trees are mostly brown.

Douglas fir trees that have Swiss needlecast infections were most prone to winter injury.

 

 

 

 

 

 

Untreated Douglas fir trees in in the landscape. Suffering from a combination of Swiss needlecast and winter injury

Untreated Douglas fir trees in in the landscape. Suffering from a combination of Swiss needlecast and winter injury.

 

 

 

 

 

Concolor fir trees planted in sites with poor drainage were susceptible to winter injury.

Concolor fir trees planted in sites with poor drainage were susceptible to winter injury.

The good news is that in almost every case the buds are fine!  So the new growth will soon help cover up the brown, winter injured needles. Be sure the soil conditions are optimum to maximize growth.  Adjust pH and fertilize as needed.

And one more…

A different type of injury that occurred during this winter. Lower branch dieback from rodent feeding on the branch bark.

A different type of injury that occurred during this winter. Lower branch dieback from rabbits and/or meadow mice feeding on bark. (They apparently have their favorites.  In this mixed planting they only munched on the Korean fir trees.)

 

 

 

 

 

 

 

 

May 24, 2012

Springtime Late Frost and Freeze Damage

2012 Brought Weather Extremes in the Spring

Lilac in full bloom weighed down by snow – April 2012

Coming off a record mild winter, we had temps in Upstate NY  that reached 80 F in mid-March, the mid- to upper 80’s F in mid-April and then a low in the mid-20’s at the end of April.  May was drier than normal for most in upstate NY and in some areas we were about inch or more below the normal rainfall in May.

 

What does all this mean for growing trees? 

Frost and freeze damage was common especially in the low lying areas of fields.  This year it was about early warmth rather than late frosts.

Concolor fir – terminal bud killed from low temps

Spruce- bud, center, killed from low temps

It seems that there are enough surviving buds on trees in many locations, so trees will able to compensate for the lost growing points and little differences will be noted when pruning this summer.

Turkish fir – buds killed due to low temps

For those managing certain pests like White Pine Weevil, which must be controlled early in the spring, growers needed to be ready extra early and it was very short window of opportunity to get treatments in place.

If possible, this year’s new transplants could benefit from irrigation

 

The drier weather, during needle expansion, may make it easier to stay on top of the fungal needlecast diseases of Douglas fir.  But the lack of normal rainfall  is also stressing the transplants that were set into the fields earlier this spring.

 

October 5, 2011

Interior Needle Yellowing

We have heard from growers in upstate New York about interior needle yellowing particularly affecting their concolor firs. From the trees we looked at on two sites in upstate NY we have not seen any diseases or insects involved, rather just natural fall needle drop.   This is one of those years where the yellowing is  visible and dramatic on many trees.  In some trees it is less noticeable because there is more new foliage to hide the interior foliage that is on its way out.  On some trees the interior needles drop with an “off-green” color which is less noticeable.  This autumn needle drop is also visible on white pines in most years, this year is no exception.

In either case with some strong winds between now and late November the offending yellow needles should be off the trees and they will be ready for the Christmas tree shoppers.