Called the “White Forest” by native populations, the Caatinga ecosystem covers an estimated 11% of Brazil and is spread across the states of Alagoas, Bahia, Ceará, northern Minas Gerais, Maranhão Paraíba, Piau, Pernambuco, Rio Grande do Norte and Sergipe. This dry forest is home to the largest populations of Carnaúba palms in the world. It also has some of the world’s most diverse plant life and its biodiversity is critically important to maintaining the variety of animals native to the region, such as the emblematic three-banded armadillo.
As part of efforts to protect natural resources for future generations, a grant of 1.2 million Brazilian reals ($370,000) has been provided to CABI by SC Johnson to help drive research in the management and control of the Devil’s claw vine (Cryptostegia madagascariensis). The exotic invasive weed threatens the unique Caatinga ecosystem, including the native Carnaúba palm (Copernicia prunifera).
“The aggressive nature of the Devil’s claw vine if left unchecked can have a devastating impact on the local diversity of plant life, resulting in a loss of native vegetation, including the Carnaúba palm,” said Fisk Johnson, Chairman and CEO of SC Johnson. “This important endeavor will help recover the health of the Caatinga forest and sustain the Carnaúba palm for generations to come.”
This initiative is co-funded by the Agência do Desenvolvimento do Estado do Ceará (ADECE), and SINDCARNAÚBA, the Carnauba Wax Refiners Syndicate of Ceará and coordinated from the Brazilian side through the Associação Caatinga. Joint funds will help establish three monitoring stations in Ceará for baseline and long-term research into the invasion by the Devil’s claw vine and develop a weed management strategy that aims to introduce and disperse a rust fungus (Maravalia cryptostegiae) to potentially control the vine.
The Devil’s claw vine is a climbing weed from Madagascar with no natural damaging enemies in Brazil. The vine is typically defined by its bell-shaped purple flowers, which usually bloom after heavy rains. Once established, the Devil’s claw vine can flower most of the year and its seeds are spread via wind and waterways. It is known for smothering surrounding plants, including the iconic Carnaúba palm, which is also an important economic plant in Ceará as a source for wax. The vine deprives plants of light and carbon dioxide, can topple trees by its sheer foliage weight, and is known to prevent access to waterways and reduce grazing land available to livestock. The milky sap, or latex, is also poisonous.
The rust fungus, which is native to Madagascar, will be assessed as a potential biological control agent by CABI in the United Kingdom to ensure that the fungus will only attack the Devil’s claw vine. Following field collection of the rust in Madagascar, stringent safety testing will be conducted under quarantine conditions in the U.K. If approved for release by the Brazilian government, the fungus is expected to cause defoliation of the plant, which will reduce plant growth, flowering and seed production – ultimately curbing the invasion in the Caatinga ecosystem.
“This investment will help to address a growing issue that is having a detrimental impact on the native flora and fauna of the Caatinga. If left unchecked, this invasive weed will continue to spread into new areas in Brazil,” said Dr Harry Evans, Emeritus Fellow, Invasive Species Management Team, CABI. “Reducing the growth and invasion of the Devil’s claw vine is essential to ensuring the long-term health of the Caatinga, and potentially of other Brazilian ecosystems.”