City Trees is a premier publication focused on urban + community forestry. In each issue, you’ll learn how to best manage the trees in your community and more!
Issue link: http://read.dmtmag.com/i/75614
Supplemental irrigation may be needed for saguaros in built landscapes. Photo by Matt Johnson Other cactus-like desert species that are used here in place of trees are ocotillo (Fouquieria splendens), Joshua tree (Yucca brevifolia), and some other Yucca species. None of them are technically cacti. Ocotillo can reach up to 32 feet (9.75 m) by one or more branches. The Joshua tree is equally tall and unusual looking but again, not a cactus. Talk about the cultural conditions and mainte- nance needs of these urban cacti. MJ: Cacti in general are drought tolerant, often storing water inside the plant during the wet season to endure the hot, dry summer. Historically the wettest seasons are late winter and monsoon season at the end of sum- mer. Saguaros store so much water that they can weigh over a ton. Golden barrel and hedgehog cacti will tolerate partial 26 sun conditions. Maintenance varies from species to species; however, the most overlooked advice is to just leave them alone! Many cacti have died from rot caused by overwatering. Others die from attempts to shape them like hedge rows. The most one should do is keep the debris cleaned out and watch for any deterioration. In an urban setting, soil temperatures can be signifi- cantly higher than the natural desert, especially near concrete or asphalt areas. Supplemental irrigation can be used in this case. Pests normally refer to insects rather than mammals due to the natural protection that most often covers cacti. One of the most interesting insects found on cacti is the cochineal, a kind of scale. From the females a deep red dye (from carminic acid) can be obtained, which has been used as food coloring, fabric dye, and face paint for the Native Americans. In small numbers, City Trees