Unless you're running a post-apocalyptic MUD, where the world is a barren wasteland, or an alien world MUD, where the creatures living there may not need oxygen to survive, you're going to have forests. They're an integral part of any economy, even in today's real world - we still need lumber for housing, furniture, and firewood. This goes doubly for a medieval fantasy-based MUD, where the people are extremely unlikely to have any technology that makes the construction of metal-based homes and furniture viable. They're also an immeasurably vital part of a world's ecosystem.

Forests can be either a burden or a joy to build, depending on how you look at them. Many people like building towns and cities more - they're guaranteed player magnets. People -will- go there. Forests, on the other hand, tend to be visited less, unless they are a good place to get experience and equipment. I strongly believe that a well-made forest is better than any city, any day, and absolutely love to make them. I'll say more on making your forest a visited place later, though.

What goes into a forest? Trees, of course, and lots of them. Depending on if your MUD has established (however loosely) climate, the trees there will vary. In a temperate climate, deciduous and evergreen trees will be everywhere - oaks, birches, pines and firs, for example. Oaks take their sweet time growing, though - so unless the forest has been there a while, keep the oaks small. Redwood trees, found in climates like that of the United States' Pacific Northwest, are the same way, but they take even longer to grow. Tropical rainforest-type trees take a very long time to grow, as well, and if they get deforested, they won't be able to support much later on. I'll talk about the option of deforestation later.

Besides trees, there are very defined layers of plant life that are in every forest of the world - ground-level vegetation (bushes, shrubs, grasses, and flowers), the trees themselves, and canopy-level vegetation (mostly parasitic plants like mistletoe, vines and certain mosses). Create these layers well, and your forest is on the way to being believable.

The underbrush is where most of your players will be wandering around - through the briars and flowers. This is also the best place to put plants that can be gathered, such as herbs that give magical affects when eaten. Make the ground level detailed, and put in everything. Some plants commonly found on the ground are (depending on the forest type) ferns, bushes (with or without berries), wild grasses, flowers, herbs, mushrooms (although not technically a plant) and mosses. Lichens may also be growing on trees or rocks. The forest floor is also very cool and shady, since the interwoven branches and leaves of the trees above will be blocking a good deal of the sunlight. Fallen leaves, pinecones, fruit and berries (all but the leaves are optional) will also litter the ground. Forest fires will clear out the underbrush periodically so as to fertilize the soil and make way for new growth.

Besides the plants, there are other "normal" things that can be found on the forest floor that can be added to make separate rooms of a forest be quite different. Rocks are an option, especially if the forest is in the mountains. Some abnormal forest growth can be put into the rooms, too, like huge clumps of fungus, or a patch of stunted trees. Beehives can hang from trees, or be on the ground if the bees in question are ground bees. Burrowing animals like rabbits will have dug holes to live in. Snakes will take over abandoned burrows. The skeletons of small forest creatures and the hollow shells of turtles can be scattered about to give the impression that the predators are hunting and not just wandering the forest, and that the animals are dying quite well without players wandering around and slaughtering them. If you want to give the impression of a changing and fluid world, rocks can have fossils of extinct creatures imbedded in them, or the fossils of sea creatures. If your forest has deer, moose or elk in it (it probably should), the young bucks will rub their horns against trees to get rid of the velvet that covers their antlers. They'll leave the velvet on the trunks, and will probably also strip some bark off. Animals that travel in herds will tend to travel one path through the forest, making a game trail. The trail will be littered with droppings (no pun intended), and will be trampled nearly plant-less.

The ground level of the forest is where nearly all of the animals worth turning into creatures (I wouldn't recommend making a termite or a gnat and then filling the area with them, but hey, it's your area) will be found, with the possible exception of birds and squirrels, which make their homes in trees. Birds and squirrels will have to go down to the ground to search for food and water, though. That said, the fauna will be determined mostly by the forest's climate. Some animals are adaptable to nearly any climate - bears, wolves, and rabbits, to name a few. Reptiles cannot survive in cold weather, but thrive in more temperate climates. Fantasy creatures such as centaurs, trolls, unicorns, wood nymphs, dryads and faeries are an option, but definitely not required (I personally prefer nymphs and dryads and faeries in my woods). Most of these creatures won't be carrying anything of worth, other than perhaps a pelt, or in the case of a unicorn, its horn. Forest-oriented people, like rangers and druids, and possibly clerics or priests who are devoted to a god or goddess of the forests, will have the more interesting things, but they'll also be much more likely to defend the forest creatures against those who want to kill them. Don't overly fill the woods with too many predators, since it takes a lot of prey animals to feed one predator animal.

Staying somewhat on the subject of animals, keep their levels and hit points reasonable. Anyone should be able to kill a rabbit or snake with one or two weapon hits, even a mage. Level forty-eight hummingbirds with twenty thousand hit points are not a good way to make your area realistic, unless those hummingbirds are as big as a house. But like I said before, it's your area. And just to reiterate another thing I already mentioned, most animals probably won't have much in the way of equipment besides their hides and furs, although a severed bear claw or deer antlers might make an interesting weapon.

The canopy will be less important, unless the forest is so thick that players can go into the branches of trees. Therefore, unless you use that as an option, you can leave the canopy less described than the forest floor. That doesn't mean that it's completely unnecessary; the tops of trees are there, after all.

Should your forest be on a high mountain, you will need to have two levels to your forest: above the tree line and below it. Below it, the forest is as I described above. However, above the tree line, things begin to thin out considerably. The floor-level vegetation will rapidly disappear, and trees will grow with less and less frequency. Fewer animals will be found here. This is mostly due to thinner air and rockier, thinner topsoil. The plants that do exist here will be hardier and wirier than those found below the tree line; temperatures are colder here, as is exposure to ultraviolet radiation due to the thinner air.

If the forest is close to a town, it will more than likely be used for lumber. The woods closer to the city can be deforested, leaving rooms full of stumps. You can also make this semi-dynamic, by slowly overwriting previously forest-filled rooms with logging operations and cut-down trees. That's much easier and less of a hassle if you use an OLC editor, both for you and your players. The ecosystem of the forest will change, too - animals leaving or dying out, for instance. Should you continue to deforest the forest for a long while, you'll be left with a field of rotting stumps, just ripe for farming after the stumps are ploughed under. However, forests will usually grow back fairly quickly if they're not kept under control, so if for any reason your town is abandoned or destroyed, the forest will come creeping back in to retake the land.

How do you attract players? A terribly simple solution is to fill it with easy-to-kill creatures that have a lot of money and great equipment, and also give a lot of experience. On a hack-and-slash or PK MUD, that's probably not going to be a problem for anyone. But in a more role-play oriented place, you'll want to make it far more interesting than just a bunch of trees and scampering little forest animals. One forest area I made involved gathering some grain from a nearby field and putting it on an altar to make a sacrifice. A druid then rewarded the player with a magical medallion. Forests have plenty of places to hide things - use that to your advantage. Some things, like a bush full of raspberries, probably won't be special enough to be turned into a -visible- object ... so don't give it a long description, put it in the room, and fill it full of berries. Holes in trees or rocks and hollow logs are some more things that can be used in this way. Add "guild rooms" for rangers and druids if those classes exist in your MUD - I use the term loosely, since it won't be a typical guild room; it will be more of a special sort of glade. Players also seem to like things that appear to have a special significance - such as an ancient stone shrine deep within the forest - but that in reality, don't do much of anything. Layering extra descriptions on them adds to the players' curiosity about them.

As is the case with all building, your choice of words strengthens or weakens your room descriptions; I have found some particularly colorful words that evoke certain images. In no real order, they are vibrant, verdant, emerald, lush, damp, dewy, flourishing and thriving. Those just are words I use for the woodlands in general; it doesn't touch the more specific plant life like flowers or mosses. A good thesaurus will give you even more words. The more varied your choice of words, the more diverse and interesting you can make your forest (and other areas) become.