[masklinn]

Eucalypts are known to not be great for topsoil quality, degrading and depleting soil (especially as they're not nutrient fixers):

> In a forest environment, SOM originates mainly from litterfall and litter decomposition. It is well known that the litter quality of eucalypts is low (Woods 1974). Eucalypt leaf litter contains large amounts of phenolics (Bernhard-Reversat et al. 2001) which are antibiotic and anti-feeding agent for invertebrate and vertebrate fauna (Waterman and Mole 1994; Harborne 1997). Eucalypt litter quality leads to low biological activity and results in a low litter decomposition rate in eucalypt plantations.

The result of using eucalypts is definitely mixed at best (https://www.aimspress.com/fileOther/PDF/agriculture/agrfood-...) but at the end GP is probably excessive, eucalypts are inferior to almost any other tree species for soil quality but they're not as bad as agricultural land:

> Our results indicate that soils in eucalyptus stands surrounding Ethiopian Orthodox church forests are more acidic and Eucalyptus may have some additional drawbacks that are not considered in this study. Though increased levels of organic matter should function have lower levels of organic matter and nutrients than soils in adjacent indigenous forest. However, there is also evidence that eucalyptus plantations exhibit higher organic matter and nutrient levels in comparison to nearby agricultural land, and no significant decrease in soil pH.