Pods of the screwbean mesquite tree, which is native to the Sonoran Desert, are edible. Read more about tasty pods at tucson.com/gardening

Photo courtesy of Peter Warren

I found these seedpods on a landscape tree and need info on what type of tree this is and how does the seedpod behave? For example, does the seedpod explode or open up? There are approximately 21-25 closed spiral pods per stem. I am making jewelry out of them and need this information.

A.: Those are fruits of the screwbean mesquite tree (Prosopis pubescens Benth). The tree is native to the Sonoran Desert, as are the honey mesquite and the velvet mesquite. The seedpods look like a tightly wound spring or a screw, hence the common name. Animals that ingest them may disperse the seeds or the seeds may lie dormant in the environment for years in their protective coat. The pods don’t explode or open up and may be well suited for your purpose. Also, these are tasty and have been a traditional food in the Southwest for many years. You can usually find the flour milled from the beans at local stores. If you harvest your own pods you might be interested in the milling events provided by local nonprofit organizations.

The leaves on my pyracantha are brown. What’s wrong?

A: Brown leaves can be attributed to a few things. The most common is under watering. If you begin to see the brown at the tips of the leaves it could be suffering from too much salt in the soil and that is a symptom of under watering. The solution for that is to water more so the salts will be flushed away from the root zone. We recommend watering every week or two during the summer to a depth of 24 to 36 inches. You can use a soil probe to determine how deep your water is going. We use a piece of rebar and push it down until we meet resistance. That is a rough estimate of how deep the water is going.

I have a huge long hedge of Texas Rangers that was allowed to grow in all at different levels, I am assuming due to water intake and such. I would like to start to trim it back in some places while only slightly trimming in others to try and even out the hedge. The issue that I see is that Texas Ranger gets very woody with no leaves only about a foot to 18 inches from the tip of the branches and in some places it would have to be taken down that far to even come close to the height of the lower plants. My question is, if I take the branches off that far down and only the woody, leafless part is left, will it regenerate those branches to have leaves again? Or will I be stuck with a level hedge that is all spindly branches and no leaves in places?

A: Pruning your Texas rangers is a good idea but you might wait until the cool part of the year so the plants will be less stressed. The reason your Texas rangers are leafless at the base of the branches is because they need pruning. You can selectively prune some of the branches back to a point of attachment to open up the plant to sun, air, and rain or you can renovate the whole shrub back to about 18 to 24 inches and start over. Either way should improve the appearance and health of the plants. If you need more information on pruning, we have a good publication on our web site, extension.arizona.edu/pima . You can search for it with the publication number AZ1499.

Peter Warren is the urban horticulture agent for the Pima County Cooperative Extension at the University of Arizona. He works with landscape professionals, urban farmers and homeowners to promote integrated pest management and best management practices for desert horticulture in southern Arizona. Questions can be sent to plwarren@cals.arizona.edu