Aspen trees ( Populus spp . ) are prone to many disease , according to theMissouri Botanical Garden . Most of these diseases are triggered by fungus . Because their bark is comparatively weak , aspen tree ( Populus spp . ) are prone to injuries . These wound spot and equipment casualty by aspen Sir Herbert Beerbohm Tree bore bit allow fungal pathogens to enter and infect the tree . Most diseases , if caught early enough , will not permanently move the tree .
Aspen Cytospora Canker Disease
Cytospora pestilence is a fungal disease due to several metal money of fungus kingdom belong to the Cytospora genus . It can affect more than 70 species of trees , including aspens . Symptoms of this disease admit discolored expanse on the barque that are chicken , orange - dark-brown or mordant in semblance ; twig and leg dieback ; liquid state , orangeness - colour ooze in the spring ; slide down utter areas of bark with disastrous pimples or speckling ; and reddish dark-brown discoloration on the woodwind instrument and/or inner bark .
The calamitous pimples are reproductive structure of the fungus . During sloshed experimental condition , long orangish threads or spores may exude out of the pimples . symptom will increase each year as the disease progresses . drouth , recent spring hoar , defoliation , weedkiller , trauma and sunscald make aspen Sir Herbert Beerbohm Tree more susceptible to this disease .
Aspen Leaf Fungus
Aspen leaf spot is also called Marssonina leaf smear , after the Marssonina fungal pathogen that do the disease . It is the most common foliar disease among aspen and cottonwoods in Colorado according to W. R. Jacobi , a bioagricultural sciences professor atColorado State University .
Symptoms of aspen foliage speckle are drear brown or black flecks with either yellow halos or bloodless centers on the leaves , but leaf petioles and terminal shoot may also be affected . These spots may merge to imprint big black piece on the leaves . Aspen leaves turn disastrous may be scattered throughout the tree diagram rather of reduce in one spot . symptom unremarkably set out to appear between July and the first fall freeze . Although this disease is not usually damaging , it can cause early leaf drop if a tree is heavily infest .
Aspen Ink Spot
Ink spot is another fungal disease , this time because of the pathogen Ciborinia. symptom include dark brownish or black arouse oval spots about 1/4 - inch long on the leaves , which may eventually make holes when the areas decrease out . septic parting may die while uninfected leaves stay light-green . This disease can cause former leaf drop and reduce tree outgrowth . Ink spot is common in the plenty of Colorado and in dense aspen stands .
Aspen Rust Disease
Rust disease is due to the fungal pathogen Melampsora. It make belittled , xanthous - orange , conceited speckle on the back side of the leaves . When break down open , these spots release an orangish liquid or gunpowder . spot are most visible in the former summertime and early free fall .
This disease can manifold quickly during plastered conditions . Although coarse , it rarely causes major trouble . However , several years of serious infections can cause growth loss in younger trees .
Aspen Leaf and Shoot Blight
Leaf and burgeon forth blight is stimulate by the fungous pathogen Venturia. It primarily affects young aspen and Tilia heterophylla . symptom first come out in the spring when irregular dark-brown or black Supreme Headquarters Allied Powers Europe appear on the leave of absence . Within a few days , the darkened tissue will turn Olea europaea green and then cause the leaves to dry out or become distorted . It will also cause canker on unexampled shoots that cause the stem to blacken and curl , resulting in malformed , shrubby emergence .
Other Aspen Diseases
A few other disease that can sham aspen let in inglorious pestilence , sooty bark canker and Snake River canker . Black canker is because of the fungous pathogen Ceratocystis fimbriata. It stimulate a large circular canker sore with layers of black bark or tissue . Because it develops slowly , it is seldom lethal .
Sooty barque canker is triggered by the fungal pathogens Encoelia pruinosa or Cenangium singulare. It come along as dark sunken region on the barque . Bark finally peels away in strips to reveal a black inner woods . Because it diffuse rapidly , it can be quite deadly .
Snake pestilence is induce by the fungal pathogen Cryptosphaeria populina. It gets its name because it cause farsighted , spiraling grayish Great Depression that circle the branches and tree that can be several foot farsighted . low eventually decompose and kill the tree within a few class .
