Help:Data editable under conditions
Some data, by nature, are only editable if you have a good reason to do it, and if you follow some rules. Not respecting rules is assimilated to vandalism and can oblige us to close your account.
Texts from written sources
The site gives access to diverse published texts, such as entire books (as the Origin of cultivated plants) or quotations. The principle is to respect litterally the text as it was published. There may subsist errors due to copying or coming from OCR, and corrections are welcome. But they should absolutely be done by checking in the original work. If the author or the publisher has left errors, they must not be corrected.
However, in the case of old texts, particular standards can be defined. In French for example, use of i/j or u/v was not the same in past centuries, and it can be decided to adopt modern usage for the sake of a better legibility. Similarly, manuscripts and incunabula often use composed signs to write some terminations ; it is better to avoid such signs.
Quotations are useful even if they are second hand. In this case, they are often faulty, incomplete or distorted. So you are invited to correct them, but always by checking in the original. As any quotation is inserted in a longer text, you may also add some omitted text, but always respecting the original.
If it has been published elsewhere, it is not modifiable. If it is an original text, you can edit it, but the author has the right to accept or to refuse your corrections.
Scientific names follow the rules of the International Code of Botanical Nomenclature. Abreviations of authors' names are also standardised. Usually, names are carefully checked with the relevant databases, such as The Plant List, GRIN or Mansfeld. In case you disagree with a name, its spelling or an author's name, please put your proposal in the relevant discussion page, and add your arguments with references (the protologue, or any subsequent publication). If you are not familiar with nomenclature rules, ask questions, but refrain from doing changes by yourself.