An invasive tree introduced decades ago to combat desertification in Gujarat Banni grasslands is now being used in biochar projects linked to corporate carbon removal deals, but experts and local communities have raised concerns over the model’s environmental impact.
Prosopis juliflora, locally known as gando baval has spread across large parts of the Banni grasslands since its introduction in the 1960s. The invasive species has displaced native vegetation and contributed to a sharp decline in fodder production.
Climate tech company Varaha ClimateAg has developed a project in Kachchh in which the invasive tree is converted into biochar using low oxygen kilns. The resulting material is intended to be mixed into soil where its carbon can potentially remain stored for long periods. Google agreed in 2025 to purchase 100,000 tonnes of carbon removal credits from Varaha while Microsoft and other companies later signed additional offtake agreements.
However, field assessments have raised questions about whether the biochar is delivering the claimed ecological benefits. Some local operators reported that biochar left in the landscape appeared to encourage the regrowth of Prosopis juliflora rather than native grasses. An agriculture expert cited in the report also said trials in Kachchh recorded lower crop production in biochar treated plots than in control plots.
Water use is another concern. Producing biochar in Kon Tiki kilns requires hundreds of litres of water per cycle a significant issue in drought prone Kachchh. Local contractors said the practical difficulties of transporting and recycling water made the proposed water saving measures difficult to implement.
Experts also warned that Prosopis rapidly regenerates after being cleared. This creates a risk that the carbon credit model could inadvertently encourage repeated harvesting of the invasive tree rather than supporting sustained restoration of native grasslands.
The report also highlights concerns over transparency in carbon credit revenues and the independence of project audits. While Varaha said its projects undergo independent verification and that communities are informed about credit revenues specific details of revenue distribution were not provided.
The case has renewed debate over whether carbon markets can simultaneously deliver genuine emissions removal and ecological restoration particularly when projects depend on an invasive species whose continued regrowth may undermine the restoration goal.