cottonwood disease.

[fugue14]

cytospora canker?

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not sure about second img.

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[John Paul Sanborn]

I've heard that cytospora is a big problem with Populus sp. in your area.

Over here we are seeing something being called Poplar Decline Complex, it may take a season or two for any number of Populus to slowly fall apart from the top down. We see cankers, leaf feeders, several types of scale... all on individual dying trees. No one has put the time and money into monitoring to see what is the chicken, and what is the egg.

One thought is the multi year drought the state has seen, with intermittent short term flooding. Established trees are experiencing lowered water tables, and cannot grown down to them, then the periodic super saturated soils that may create anoxic conditions.

 

[fugue14]

It seems like 90% of the cottonwoods I see in Colorado are dead or dying. I've been working with them for two or three years now and there is nearly always a more visible orange/red jelly looking cytospora in all of them. I was also told that since they grow so rapidly they save little energy for defense against diseases etc.

 

[John Paul Sanborn]

It seems like 90% of the cottonwoods I see in Colorado are dead or dying. I've been working with them for two or three years now and there is nearly always a more visible orange/red jelly looking cytospora in all of them. I was also told that since they grow so rapidly they save little energy for defense against diseases etc.

Common strategy for riparian plants, grow fast, seed out early, fall over and fertilize the soil.

Do a serach for poplar or cottonwood decline, there is a lot of info on the decline of western prairie and foothill poplar-forest ecosystems due to the damming of the riparian zones. The lack of silting has interrupted the nutrient cycle, they do not get the water they used to, there may even be a change in animal/insect populations that is effecting the plants.

Cytospora usually wind and soil born, over here they say that squirrel chews can cause infection courts. Most literature say that any wounding during sporation seasons is susceptible. Some lit. speculates on insect vectors, especially in the upland P. tremuloides population.

over here the Colorado spruce is hit hard by cytospora

 

[Toddppm]

Anybody else get a virus trying to download when clicking the pictures linked to in this thread :at-wits-end::eyeroll:

 

[John Paul Sanborn]

Anybody else get a virus trying to download when clicking the pictures linked to in this thread :at-wits-end::eyeroll:

Must have been from the pop-up, I run a blocker. Though I'm running a scan right now......

 

[sgreanbeans]

We see cankers, leaf feeders, several types of scale... all on individual dying trees. No one has put the time and money into monitoring to see what is the chicken, and what is the egg.

One thought is the multi year drought the state has seen, with intermittent short term flooding. Established trees are experiencing lowered water tables, and cannot grown down to them, then the periodic super saturated soils that may create anoxic conditions.

We had one of those this year, HO/Neighbor had ripped out old drive and dug in a new one about 2 ft lower, 5ft away,about 4 years ago. I warned him! Tree declined rapidlly, then seemed to turn around, then dropped off again last year with all those same ailments, whole top half of canopy had canker and galls everywhere. Do you think the stress of the "root prunin" was a precursor? Seemed to recover, but I think the others had already started and tree was too weakened to defend and ultimately succumbed.
Easy job, little travel time as it was across the street! Lunch at home, on the grill!

 

[John Paul Sanborn]

Construction damage is usually a primary stressor.