The article started as a misplaced page, as it was added when hexxit alpha had thaumcraft which added silverwood trees. Strangely enough, even though thaumcraft isnt installed it is claimed natura has added its own silverwood tree, I looked through the entire page of code natura provides... I cant find anything about a silverwood tree. I know silverwood trees exist in hexxit because i've seen them and isolated one to perform some experiments to see if I could gather additional information, but I couldnt find anything... I simply added a picture of what i've found.
If we're going to have anything Thaumcraft related we may as well include all thaumcraft info even though it isnt a part of the mod pack anymore. If the wiki was around when Thaumcraft was in the mod pack and pages had already been created revolving around Thaumcraft, I would say keep it and I would update the templates for mob/item/block to add a "Removed In" field to let people know it is no longer a part of the mod pack. However, since this wiki doesn't have any pages on thaumcraft related material (outside of the silverwood tree for one reason or another) I see no reason to keep such information.