Colorado_medium Colorado Extension

Questions received for Colorado through Ask an Expert.

(This group currently has 1 expert available to answer questions)

Questions asked to this group

Lombardy Poplar suckers

We have four older Lombardy Poplars with numerous suckers. Will the suckers damage the parent trees, or will they become a grove, like Aspen trees? If we have to remove the suckers, what is the best and least toxic method? Thanks! -G2.

Delta County Colorado Posted 11 minutes ago

Beef cattle and alfalfa

We have about 20-30% alfalfa in our fields for the cow/calf operation. We have heard mature alfalfa is safe and young alfalfa causes bloat. So far we have only grazed after the first fall freeze. We would like to have them graze the fresh forage, but wanted a professional opinion. Also, do bloat blocks work?

Elbert County Colorado Posted about 3 hours ago

Aspen leaf curl

I have an aspen tree that is about 26 years old, 25" diameter, and 25 ft tall. Last summer leaves started to curl, turn black and drop off the tree in somewhat large numbers. This year, the tree leafed-out like a champ, but then about 10 days ago I started to see a few leaves curling (but not turning black) and shortly after falling to the ground. I can see more curling is occurring, but it is a very vert small percentage. Attached is a photo of a couple of curled leaves picked up off the ground, and hopefully you can give me an idea of what is causing this and how to treat it. Should note that the tree also has a couple of visible areas (one about 3" sq and one about 3"x10") what I believe may be called cytospora-canker. I have heard there is no treatment for this canker and wonder if the leaf curl could be connected to it. There is no sign of spots or other tell-tale signs of diseases I see on your web site, the leaves just curl-up and die. Thanks.
PS: Should note there is not any aphid honey or other obvious sign I am familiar with that indicates aphids.

Boulder County Colorado Posted about 12 hours ago

splitting trunks

How much water does an aspen tree require or how to care for a distressed aspen tree? The trunks of our aspen are splitting and weeping. ..what to do?

Boulder County Colorado Posted about 15 hours ago

Is this evidence of insect invasion?

This gossamer, cobweb-like stuff is all over my flower garden. It seems to be especially detrimental to my prized Oriental lilies, causing their buds to wither & drop. I sprayed yesterday with Bayer's Insect spray for Roses & Flowers, but it hasn't had much of an affect. I found the web pictured on some penstemons that had passed. What is this stuff, & how do I combat it?

Mesa County Colorado Posted about 16 hours ago

Rocks and roses

We have garden with a variety of plants and several roses. We have had mulch, but it has disintegrated and has never kept the weeds out. Does putting rock in the area hurt the roses? Will the rock create too much heat for the roses? Thank you Christina Gonzales

Jefferson County Colorado Posted about 16 hours ago

Aspen suckers destroying my lawn

My next door neighbor has a stand of aspen trees that are putting out enough suckers to make a mess of my bluegrass lawn. I do not want to injure their trees but I do want to get the suckers out of my grass. Is this possible?

Garfield County Colorado Posted about 16 hours ago

Tree of heaven

My neighbor has numerous tree of heaven trees growing on the property line next to our property. I now have roots and suckers established throughout my yard. What advice do you have on getting rid of these suckers in my yard? Do you have any materials I could use to convince my neighbor to remove these invasive trees from his yard? If he agrees, what is the best removal option? Thank you. Lois Witte

Jefferson County Colorado Posted about 19 hours ago

The west side of my blue spruce is browning

I have a 5 foot blue spruce which is browning on the south west side. The previous pine tree in this spot did the same thing, so I'm thinking it's the heat and sun. One person recommended deep root feeding. Is this a helpful thing to do? Any other suggestions? (My neighborhood will not allow me to put a fence or any other solid shield there to keep sun off the plant.)

Douglas County Colorado Posted about 21 hours ago

ID-ing a weed in a South Boulder garden

Hello! Attached are two photos - one of a small 6-leafed weed that's spread so much it's verging on a being a full-on groundcover in a few spots, and another of a vine-like root that I believe is connected to it. When turning over soil in a backyard garden I've been working, I've come across a lot of the large roots (many thicker than the one in this photo). At first I worried they were tree roots that had made it into the large raised bed, but that doesn't seem to be the case - they're usually just a few feet long and seem to be connected to the little weeds. Or to be remnants from previous years. I've been pulling them out when possible (if there's not something planted nearby that would be too disturbed). With others I've just sliced through them with a shovel to hopefully kill them and pulled the ends to the surface so I can easily find and remove them after the growing season's finished up. Can you identify what I have here and advise on the best course of action? I've been removing the surface-level weeds to try to keep them from choking vegetables out & "stealing" water, but a neighbor with much more gardening experience advised asking you in case they're actually beneficial in some way - I believe she speculated about something to do with nitrogen. Should I keep removing the weeds by hand or with a solution of some sort? Or should I leave them be? Thanks in advance for any information or advice you can share! Best, Sierra Stults

Boulder County Colorado Posted 1 day ago