Plant Trademarks

In passing I mentioned the matter of trademarks for plant names. In the past we didn't have to deal with trademarks in succulent plants; that was the headache for the rose people. But now they're all over the place. Just what is a trademark and how is it appropriate in relation to the names of plants? We already have a system for naming plant cultivars by simply publishing the cultivar name (which must be in ordinary language). Such names can be used by anyone, freely.  Principle 4 of the International Code of Nomenclature for Cultivated Plants 2004 states that "Names of plants must be universally and freely available for use by any person to denote a distinguishable group of plants. In some countries, plants are marketed using trademarks. Such marks are the intellectual property of a person or some corporate body and are not therefore freely available for any person to use; consequently, they cannot be considered as names."

But now we have businesses trademarking cultivar names, though it's my understanding that the US Patent and Trademark Office (USPTO) is opposed to the use of trademarks for cultivar names of plants. Remember. A TM on a plant does not prohibit the propagation and redistribution of a particular plant. Plant patents are available for that purpose. And if the TM  is applied to an already accepted cultivar name, it certainly is inappropriate if not illegitimate.
(The above is my opinion and my rant. I'm not an attorney, so don't consider this legal advice.)