Ask Mr. Smarty Plants

From a previous Mr. Smarty Plants answer, answered by our Senior Botanist Dr. Damon Waitt,  here is a description of "fasciation," which we believe could be the cause of the strange growth on your bluebonnets:

"This sounds like a case of fasciation, a plant developmental anomaly in which it appears that stems, flowers, leaves and/or fruits have been fused. It is uncertain whether it is genetically determined or caused by disease or some other sort of trauma to the plant. It does appear that there may be an inheritable tendency toward fasciation that may be triggered by environmental conditions such as temperature, crowding, insect attack, disease or wounding of the plant. Some fasciation may be caused by bacterial or viral infections. Fasciation bacteria survive on infected plants and debris and they spread in water and through wounds. If bacteria is to blame, the solution is good sanitation and use of pathogen-free plants. The University of California Integrated Pest Management website reccomends you "Avoid injuring the base of plants, especially when plants are wet. Keep the base of plants dry. To control fasciation to all potential causes, do not propagate or graft symptomatic plants. Remove and dispose of infected plants, or prune and dispose of distorted tissue and do not proagate from those plants." Here is a photo of fasciation in Texas Bluebonnet."