![]() Wind breakage of stems weakened by rust galls. Severely infected oak leaves may have yellow spots but symptoms on oak leaves are usually not noticed.įigure 7. On the underside of infected oak leaves, the fungus produces fine, inconspicuous hairlike structures (Figure 3). Oak leaves become infected when the first flush is expanding in the early spring. Oaks in the white oak group are rarely infected. ![]() The most commonly infected oak species in Alabama are water, laurel, willow, and southern red. These yellow spores are no threat to the pine but rather serve to infect the alternate host, an oak. Many galls, which appear in late March to early April each year, may be present on a tree making the infection conspicuous. In the early spring, these galls produce orange-colored spores in bladderlike blisters (Figure 2). The galls are elongated with deep fissures. The fungus produces spindle-shaped galls on branches or main stems of pines. After cross fertilization within the pycnia, pyciospores establish the perennial gall that can produce the orange aeciospores again each spring for decades. Immature gall producing pycia that may cross fertilize the infection.Ī few months after basidiospores infect pine, another spore stage is produced, pycniospores (Figure 4). Life Cycleįusiform rust is caused by a fungus that produces five different spore stages and requires both an oak and a pine tree to complete its life cycle (Figure 1).įigure 4. In spite of these improvements, fusiform rust still costs the forest industry millions of dollars annually. These efforts appear to be working and long-term forest health monitoring plots now indicate that disease incidence and severity are decreasing throughout the host range. Since the 1960s, genetics programs have worked to select rust resistant varieties, and pathologists have sought the best ways to deploy the resistance by defining rust hazard areas across the South. On the 13.9 million acres of southern forest land, an estimated 10 percent of the trees have potentially lethal cankers. Today, despite spending hundreds of millions of dollars to minimize its impacts, fusiform rust remains the most economically important disease of pine in the southern United States.Īlthough the fungus infects all southern pine species from Texas, east to Florida, and north to Maryland, it is most severe on slash ( Pinus elliottii) and loblolly ( P. With the extensive planting of susceptible pine and an aggressive fire suppression policy that increased the oak abundance, the disease became widespread throughout the southern United States in the 1970s. The development of the pulp and paper industry in the 1950s, however, spurred the use of plantation forestry throughout the South. ![]() fusiforme) was so rare that forest pathologists had not yet developed an interest in the tree disease. ![]() As participants were practicing empathy they started to ‘see’ their own roles in making change happen.In the 1940s, the occurrence of fusiform rust ( Cronartium quercuum f.sp. The AJISO team facilitated NPA members to deeply reflect and ‘feel’ for themselves how a violence victim must feel to see her perpetrator get away with his crime. The sacred plant had turned into a tool that enables impunity of sexual crimes. No one would dare to take such a case to court because of the perceived power of the Isale plant. A rapist who takes Isale leaves to the parents of his victim can expect to be forgiven and the case is closed. Unfortunately, the Isale customs has become a means to silence victims of sexual violence and their families. As participants reflected about drivers of GBV and child abuse they shared how the use of traditional cultural practices has changed over time: In Chagga communities the Isale tree has been a sacred plant and symbol of hope, protection and reconciliation. In February 2021 we supported our partner AJISO in facilitating a reflective training to the NPA committee in Kirongo Samanga ward in Kilimanjaro. Through a partnership model UZIKWASA shares reflective social change approaches with interested CSOs in Tanzania.
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