Plants on Vulcan
What fragments of endemic plant life remain on Vulcan support the geological evidence that a great natural disaster occurred around 10 thousand years ago. 1, 2 Some plant orders are endemic to the planet in a way that would not be possible given limited means of transportation of progeny across continental deserts. There is also a fossil record of the ancestors of current plants in locations that would not support them now. 4
Populations on oases would behave almost like those on islands in the ocean, causing divergent evolution and unique forms of plant life. Plants confined to large oases are surrounded by deserts that are difficult to traverse, and populations would begin to evolve and fill niches in that location, becoming different from populations in other locations with which they would not cross-populate.3 However there is some limited transfer of plant material across and through deserts. Animals that carry seeds in their fur, feathers and dung are of course important. Many plants rely on shavokh to first consume and then carry seeds to new oases.4
Subterranean plants are a little known order on Vulcan, which take advantage of relative moisture and compensating for reduced levels of light in caves, lava tubes or just underneath the soil. Those who know the signs can gain emergency supplies of water from subterranean plants by knowing where to dig.4 Carnivorous plants are more widely known about such as the d'mallu (vine) and sir-soss'im (tumbleweeds) 1
The soils in deserts can be rich simply because materials important to life decay, and then are not used due to a lack of water. This is no exception on Vulcan, which also has relatively young soils throughout the planet, renewed by frequent volcanic activity, even in the face of elevated levels of ionizing radiation from Vulcan's star as compared to Earth, which does damage soils somewhat. 4
Carnivorous plants are after nitrogen and copper that can be available from animals but even more importantly the water that is needed to unlock those resources. Almost all plants on Vulcan are adapted to elevated levels of salts in the soil that are of great interest to scientists on Earth. 4
Herbs, Poisonous and Medicinal plants 5
Gal-en-du'un - dream moss, a lichen that produces a smoke when burned that is narcotic to inhale
Birkeen - a sweet Vulcan herb, often used in flavouring water
Saya - which makes an intoxicating beverage
D'lechu - a fruit which is used ceremonially for it's narcotic juice
Food plants 5
Barkaya marak - a peanut like legume made into soup
Fori - a vegetable
Hirat - grape-like vine
Kap-yar - a wheat-like grain
Kaasa - a blue-green fruit
Khara - a desert bush with edible fleshy stem cores
Mashya - a tuberous vegetable
Pla-savas - the famous bluefruit
Savas dukal-yel-travek - Globefruit
Yon savas - firefruit
Due to the hostile nature of the planet's ecosystem and careful screening at customs there are no known invasive plants species from other planets causing problems on Vulcan. Few introduced crops are able to be grown intentionally either for food or any other industry except under closed-loop systems with higher humidity levels than background. 4
1 The Way of Kolinahr Sourcebook Paramount Pictures
2 Spock's World Diane Duane
3 the Origin of Species Charles Darwin
4. Headcanon :)
5 Vulcan Language Dictionary www.starbase-10.de/vld/