Is it illegal to pick bluebonnets in Texas?

The Texas Dept. of Public Safety published a press release regarding bluebonnets in 2015. While it states that "there is no law against picking the state flower," it urges you to consider other laws and other issues that might come into play — criminal trespassing, impeding traffic, damaging rights-of-way, etc. Also keep in mind that apart from state law, local governments (e.g., counties, municipalities) can enact ordinances that might apply within your jurisdiction.