Tillandsia and Vriesea have hard dry seed pods, and when these ripen they suddenly split open where the seed blows away on the wind. Lack of attentuion to the ripening and the see will be lost.
The image shows the fine seed of a Tillandsia tricolor ready for harvest.
In nature the seed becomes airborne and flies off in the wind. If it lands on a host plant and with the right conditions it will germinate. Sometimes the seed that lands underneath a branch has the advantage of not beingburnt by the hot sun. Experiments have shown that Tillandsia seed germinated in Aggar Aggar produce roots thatb grow upward,.
As seed pods of Tillandsia begin to rippen I shift them indoors to a location where the seed can not blow off in the wind with a specially designed tray underneath them so as to catch any stray seed that might fall down, up the sides of the tray is a fine net.
With larger Tillandsia and Vrieseas that I can not move indoors, I tie a small piece of stocking over the seed pod to catch any seed.