'sparse trees' is correct and usable in written English.
You can use it when referring to trees with sparse canopies or to trees that are widely spaced and not growing in dense clusters. For example, "The landscape was dotted with sparse trees and wide, open fields."
Herds of goats chew the bare dirt under sparse trees.
Along this particular stretch of the Via, it was a rocky, two-foot-wide trail with sparse trees on either side and the odd dab of color from some thin-stalked wildflowers bobbing over the dust.
Surveyed plots covered a gradient of tree densities (according treatments) from unlogged plots, 50% logged trees, 66% logged trees, and surrounding areas of open landscape with sparse trees.
We assess the direct effects of temporary shrub encroachment under the cover of mature sparse trees on overall plant and habitat diversity.
Low-density stands (100 150 tph) with sparse trees and rare big trees were in close proximity (0 36 m) to tracks and lodges.
The steep slope of wδ18O from Yaounde to the Ndop plain (Fig. 7b) with deciduous shrubs and sparse trees suggests the interplay of altitude and continental effects.
A sparse tree cuts the center of the photograph.
The Karakorams have upper and lower tree lines, the upper delimited by cold and the lower by aridity; within these lines is found only degraded, sparse tree cover.
In a pixel with a sparse tree canopy for example, differencing a vegetation index will measure a small change due stand-replacing fire.
Prior to 1850, many areas currently occupied by high-density pinyon-juniper woodlands, with their degraded soils and depauperate understories, were very likely savannas dominated by native grasses and forbs and containing sparse tree cover scattered across the landscape.
The Eastern shore had fewer discrepancies, probably because of sparse tree cover and lower biomass.
