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saguaro without arms may grow no arms during the entire time a buyer owns a property. But the loss of a large-armed saguaro compounds the purchase price with the cost of removal and often, replanting. As in any transplant, the vast majority of roots are left behind. Saguaros have a tap root that tapers to pencil- width in about 2 feet (.61 m). It is important that the entire tap root be retained undamaged. Broken tap roots are often fatal. What is not as well understood by movers is that the lateral roots that are pencil-size and larger should be retained as well. Saguaros are mainly dug bare root and can be left open to the air for days without detriment. New roots are regenerated at the cut ends—not at a single terminal meristem as with many palms. Lateral roots taper to pencil-size, but 24- to 30- inch (61 to 76 cm) lateral root lengths may be neces- sary for successful transplanting. In many instances, when dug, saguaro roots are removed, leaving a stem like a pencil point. When the larger roots are damaged or removed, it is difficult for saguaros to re-establish. Moving large, thorny saguaros is difficult. Saguaro mov- ers will often bring jackhammers and, less often, tren- chers to dig to the depth of the tap roots. The most effec- tive moving equipment especially for large transplants is a truck-mounted hydraulic lift. This involves a rated truck with a padded beam called a cradle connected to a hydraulic system to which the saguaro main stem is strapped down and tilted over the cab for transport. Cranes are not effective because the soft, fleshy stem and spines will be injured and disfigured by slings, reduc- ing salability and creating infection sites. The process is reversed at the planting site where the body of the cactus is held upright in the hole until soil can be packed under the roots and the cradle can be removed. At this point many movers eliminate the final two steps, reducing survival. Because the tap root and laterals are only about 2 feet (.61 m) long, and the plant should be planted at grade, a triangulated support system of lumber padded at the stem or a guy wire anchor system on a hose- covered wire ring is necessary to hold up the larger sagua- ros. If a recently planted large saguaro has no support system, it was planted too deep. Saguaros 6 or 7 feet (1.8 to 2.1 m) in height need no more support than a single vertical stake installed with a pad against the stem. Long ago movers determined, incorrectly, that trans- planted saguaros should not be watered or they would be killed by fungus. However, roots penetrate moist soil eas- ier than dry soil. Saguaros are no exception and water is needed for essential metabolic functions. With the major- ity of the root system gone, water must be supplied. The soil should be allowed to dry down for a week or two and then watered again until the root system is re-grown. Saguaros with bird holes and missing arms are not as desir- able as intact stems. During a move, a system of padded 2x4 www.urban-forestry.com Resources Arizona Native Plants Administrative Rules & Laws 2008 Arizona Department of Transportation - Saguaro Survival Study – unpublished Desert Botanical Garden - Saguaro Transplant Study, unpublished communications, lead inves- tigator, Cesar Mazier Harris Environmental Group - Saguaro Cactus Transplant Survival Study 2004 or 2x8 lumber tied to arms in an informal scaffold prevents loss of arms when the plant is bounced on rough roads or in the wind. Although it is advisable to retain the soil on the roots of large saguaros as in a boxing transplant, it is difficult because the weight of the rootball will snap the trunk if not supported. Hydraulic trucks are not outfitted to support a rootball. They can be craned with box onto a truck but laying the stem down subjects it to cracking and fatal breakage. There are some signs to look for in large saguaros indi- cating they are past their prime. As they age, the base of the trunk will begin developing dark, corky bark instead of chlorophyll-impregnated cells. The trunk and even arms will become brownish as the ability to make chlorophyll is decreased with age and stress. The tip of the main stem and the arms should be thick and rounded with tightly massed spines. If the tips of the stems are narrow and relatively pointed, the saguaro is declining. Some final observations: Many movers believe fungus is the agent that kills transplanted saguaros, and to that end, many apply sulfur to roots and backfill. The fatal disease of saguaro is an Erwinia, a bacterium, and sulfur is ineffective against it. The truth is that removing too much root, planting too deep, and withholding water is more commonly fatal. Saguaros much larger than 20 feet (6.1 m) are seldom moved, as they are deemed too difficult to move in most cases. Saguaros grow in well-drained terrain, so moving them to heavy clay soils spells early death. Smaller saguaros need to be initially protected from the sun with shade cloth, and larger saguaro should be installed with the original compass orientation because the north side may not be adapted to the summer sun. Moving saguaros during warmer weather when root regeneration is active will be more successful than cool season transplanting. Many of the techniques in use today are believed to have been applied centuries ago by Native Americans in the employ of Spaniards. There has been very little science applied to saguaro transplants until the last decade. Progressive cactus movers have embraced this science, while the others are still moving saguaros with very little ultimate success. 13