Autotrophic organisms are a ubiquity and a necessity for all planets bearing complex life. Kerbin is definitely no exception to this rule, as photosynthetic organisms, such as plants, cover almost its entire surface. Most Kerbinian plants are green, as Kerbin orbits Kerbol, a star not too dissimilar from our own. Plants first evolved on Kerbin at around the same time as many animal phyla began to emerge, seedling on the underwater rocks, before the main clades of plants emerged onto land. Of course, algae have been around for millions of years before, and this is indeed the next step of Kerbinian plant evolution.
Trees have evolved on Kerbin multiple times. These large plants are composed of a trunks and branches made of wood, which is slightly softer than the wood of Earth trees, but is no less strong. Unlike the sclerenchyma cells of Earth trees, those composing Kerbin wood are still alive in some capacity, with the outer wall of the trunk forming a hard layer of a cellulose like material, that is a bit like an exoskeleton, which helps support the tree. On each tree, there are leaves or other photosynthetic organs, although the size, shape, number and arrangement can vary from species to species, or from clade to clade.
Here are two most well known trees on Kerbin.
Gumtree
The Gumtree and the clade to which it belongs to are among the most diverse group of trees on Kerbin. The Gumtree is among the most well known. Reaching heights of 5 metres on average, the tree is pretty much normal for its clade. It is one of the species of trees known for producing fruit. The Gumtree gets its name from its pinkish fruit, which are fleshy and weirdly chewy, almost like chewing gum. There are many leaves covering the gum tree, supported by the wide trunk.
The fruits are produced by flowers on the Gumtree and its kin, which rely on pollinators to spread pollen. This is the mode for reproduction for not just the Gumtrees and their kin, but all flowering plants. The Gumtrees, their kin, and some less closely related plants seem to take this a step further by producing these fruits, which are eaten by various frugivores, which end up consuming the seeds within the fruit and excreting them somewhere else, so that a new plant can grow anew.
The Gumtree belongs to the largest plant phylum on Kerbin, Anthophyta, the planet's equivalent of Earth's Angiosperms. This phylum contains around 300,000 species, and the Gumtree is one of them.
The Gumtree is almost widespread, but it generally grows in temperate climates, with average rainfall rates and light exposure. The trees of this zone thrive in it. They serve as homes for many animals, including Tree Cats, Klizords, including Cracktails, Kerbopithecids, and other weird and bizarre animals. But there is a particular kind of tree that helps form more extravegant communities
A drawing of a Gumtree. To the right side is a small bush. There is also a Semantic Wormsnout Trunksucker (Vermirhynchus semanticus) flying towards the tree.
Domain
Eucyta
Kingdom
K-Phyta
Subkingdom
Autophyta
Superphylum
Neophyta
Phylum
Anthophyta
Class
Frutapsida
Order
Frutales
Family
Kerbodendraceae
Subfamily
Kerbodendraideae
Tribe
Kerbodendrapheae
Genus
Kerbodendrus
Species
K. vulgaris
K. gumae
Needle Tree
The Needle Tree is a massive plant, among the tallest living things on Kerbin. Reaching heights of 60 metres, or sometimes more, the Needle Tree is the basis of the most diverse ecosystems of the planet. The trunk is tall and wide, with sturdy rows of relatively large, hibernating sclerenchyma cells. In fact, the oldest of these do indeed die, giving the trunk a harder structure. On the top of the trunk, there are 2 dozen or so huge leaves, almost shaped a bit like needles, pointed in their appearance, a fact from which the Needle Tree derives its name. the leaves are somewhat translucent, allowing each and every cell in the leaves to access light and perform photosynthesis. the leaves are packed with the palisade cells which are intern packed with chloroplasts, something that every other plant on Kerbin has going for it, but not to the degree of the Needle Tree and its relatives.
Near the top of the trunk, below the leaves, are two projections of the trunk that terminate in gametangia, organs that produce gametes. Needle Trees are hermaphroditic, meaning that they have both male and female parts. But, they have separate male and female gametangia, making them monoecious. However, as there is very little wind able to access the rainforest, the Needle Trees make use of a ballistic mechanism, their male gametangia shooting light weight pollen grains at the female gametangia, which then take in any pollen grains that make it. The pollen grains enter the female gametangium then go on to fertilise the eggs with in, which form into seed like forms. The female gametangia then expel the seedlets at a high velocity, in the hopes that the seedlet will land in a favourable spot, with enough light and nutrients in the soil. But this is a rainforest, so this method of reproduction is slow, and may be repeated only once in a century or so, right when the old trees are about to wilt away and die. This happens gradually though, and not all the plants die every 100 years.
The Needle tree, along with its relatives, are most often found in the rainforests of the eastern side of the Oriental continent, where Typhoons of the Loveheart Ocean pour tens of millimetres of rainfall per month. This wet and warm climate is very favourable for this plant and it's relatives, as there is a massive amount of sunlight in the equator. The trees form the perfect habitat for many different types of animals and other organisms, including forms that may have gone extinct without them.
The Needle Tree is part of the phylum Megalophyta, a clade consisting of almost entirely large, hard plants, whose barks are lined with a bone-like layer. This allows them to get to the massive heights that define many members of this group. Many plants of this phylum are relatively large and primitive looking, compared to the other plants, with the order Titanales being the most advanced. The phylum first evolved at around the start of the Karbonian Period, and have been the main trees for around 320 million years, giving rise to the largest plants on Kerbin, even after the time when many Anthophytes began to evolve into tree like forms. Megalophytes are still the dominant groups of trees, and they will likely continue to be so for long time to come.
A drawing of a Needle Tree, or a similar plant. Background is omitted.
Domain
Eucyta
Kingdom
K-Phyta
Subkingdom
Autophyta
Superphylum
Neophyta
Phylum
Megalophyta
Class
Megaspermae
Order
Titanales
Family
Pteraceae
Subfamily
Pteraideae
Tribe
Pterapheae
Genus
Pteris
Species
P. orientalis
P. hawaiicaledonensis