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Life forms are key to understand the changes in species composition and vegetation types in space and with succession over time. We asked how life forms from dry and wet regions differ in their leaf traits and trait hyperspace (i.e. trait variation) in early tropical forest succession on abandoned agricultural fields.We compared 324 early successional species from six life forms (herbs, grasses, vines, lianas, shrubs and trees) that occur in the first 5 years of succession on abandoned fields in Ghanaian wet and drought deciduous tropical forests. We measured 12 leaf traits that are important for carbon, water and nutrient use.A principal component analysis showed that 46% of trait variation is captured by a two‐dimensional spectrum of plant form and function: a leaf economics spectrum underpinning fast‐slow growth strategies, and a leaf size spectrum related to plant size and heat balance, which underlie species sorting along environmental gradients in space and time (during succession). Herbaceous and woody life forms had different leaf economics strategies: herbaceous species had more acquisitive trait values (e.g. higher leaf nutrient concentrations) that increase resource capture and use efficiency whereas woody species had more conservative trait values (e.g. higher leaf mass per area) that increase resource conservation. Regardless of life forms, dry forest species and deciduous species had more acquisitive trait values than wet forest species and evergreen species as they maximize their growth during the shorter growing season. The trait hyperspace was larger for woody life forms especially in wet forests.Synthesis. Herbaceous species had 'faster' leaf economics trait values and, hence, rapid carbon gain, explaining their success earlier in succession. In contrast, woody species had 'slower' resource conservation trait values that increase persistence, thus explaining their success later in succession. Deciduous species especially in a dry region had higher leaf nitrogen and phosphorus concentration to attain faster carbon gain to cope with a seasonally harsh environment. The trait hyperspace was generally smaller in the dry forest, as there are more deciduous species, and as a result, there is less variation in leaf lifespan and associated traits. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

At best, conservation decisions can only be made using the data available at the time. For plants and especially in the tropics, natural history collections remain the best available baseline information upon which to base conservation assessments, in spite of well‐documented limitations in their taxonomic, geographic, and temporal coverage. We explore the extent to which changes to the plant biological record over 20 years have changed our conception of the conservation importance of 931 plant taxa, and 114 vegetation samples, recorded in forest reserves of the southwest Ghana biodiversity hotspot. 36% of species‐level assessments changed as a result of new distribution data. 12% of species accepted in 2016 had no assessment in 1996: of those, 20% are new species publications, 60% are new records for SW Ghana, and 20% are taxonomic resolutions. Apparent species ranges have increased over time as new records are made, but new species publications are overwhelmingly of globally rare species, keeping the balance of perceived rarity in the flora constant over 20 years. Thus, in spite of considerable flux at the species record level, range size rarity scores calculated for 114 vegetation samples of the reserves in 1996 and 2016 are highly correlated with each other: r(112) = 0.84, p <.0005, and showed no difference in mean score over 20 years: paired t(113) = −0.482, p =.631. This consistency in results at the area level allows for worthwhile conservation priority setting over time, and we argue is the better course of action than taking no action at all. [ABSTRACT FROM AUTHOR]