CACTUS IN SOUTHERN TIGRAY: CURRENT STATUS, UTILIZATION AND THREAT - L. Habtu1 & M. Fetene2

¹Tigray Food Security Office, Mekelle, Ethiopia
2 Addis Ababa University, Department of Biology, Addis Ababa, Ethiopia

Cactus pear (Opuntia ficus-indica) is expanding throughout southern Tigray in Northern Ethiopia.  Its current status, uses and potential threats were investigated at Tabia Kara Adishabo of the Raya Azebo Wereda, using socio-economic survey and environmental analyses.  Knowledge and perception of farmers of cactus pear was gathered by means of questionnaires and discussions with elders.  Vegetation was sampled using quadrants from areas with differing cactus pear infestations. Soils sampled from different sites (dense cactus pear area, cleared cactus pear area, vegetated area, arable land and decayed cactus pear piles) were analyzed for percentage organic matter, total nitrogen, available phosphorus, pH, electrical conductivity (EC), and bulk density at 0-15 and 15-30 cm soil depth.  Despite heavy infestations invading potential crop fields, about three quarters of households who participated in the interview appreciated the economic value and presence of cactus pear in the area.  Farmers indicated that the plant is utilized primarily as food for human consumption and as feed for livestock, especially during periods of drought.  The main concerns of farmers were that the thickets were harboring crop pests and that crop land was being invaded.  The vegetation study indicated that the average cover for ten dominant woody species declined as infestations of cactus pear increased. On the other hand, the number of woody juvenile individuals per hectare at three sites showed significant differences among cactus pear free, intermediate, and completely invaded sites. Regeneration and recruitment of juvenile woody species was found to be higher in the high cactus pear cover area than in cactus pear free area. High organic matter content was recorded from dense cactus pear areas, which was significantly different from the other sites at 0-15 cm soil depth. There was no significant variation for total nitrogen in both soil depths at different sites. Significant variation among sites was observed for available phosphorus at both soil depths. Soil samples from decayed cactus pear piles and dense cactus pear areas showed the highest mean available phosphorus values at 0-15 cm soil depth, which was significantly different from the other sites. Significant variation was also obtained for EC and soil pH in soil samples of decayed cactus pear piles at both soil depths. The study showed that, although the fertile Raya plain is becoming progressively more infested with cactus pear, no coordinated attempt is made in terms of control.  It is concluded that the expansion of the cactus pear stands also needs to be checked. Nevertheless, it should be noted, that in the absence of alternative land uses, including reliable irrigation schemes in these areas, the benefits of cactus pear is vital for the survival of humans and livestock in view of prevailing conditions of insufficient and unreliable rains and recurrent droughts.