But, if you're like me and want to encourage Texas wildflowers to grow in your yard, you may want to weed selectively. The following wildflowers are beginning to sprout right now and if you leave them be can be a nice addition to your yard later.
Wild primrose looks similar to dandelion when it first sprouts. The leaves are somewhat ruffly at the edges, as you can see in the picture below (though, admitedly, some of what you see there was caused by insect nibbles. But the wrinkling at the edges is not caused by that, from what I can tell.
This is what they look like in the spring!
Goldenrod doesn't bloom until the fall, but its a slow grower. I'm noticing new plants sprouting in my garden now. At this early stage it looks similar to common plaintain...but plantain will soon become hairy, while the leaves of goldenrod remain smooth. The edges of goldenrod leaves are serrated.
In the fall Texas Goldenrod provides bunches of showy yellow blossoms. According to Wikipedia, Goldenrod is unfairly blamed for causing hayfever, which is actually caused by ragweed which blooms at the same time. Ragweed's pollen is airborn, while goldenrod pollen is too heavy and sticky to be blown far from the flowers (and mainly transported by the bees it attracks). They are invasive, however, and hard to remove once they're full grown, so keep that in mind when deciding whether to let them in your yard.
(NOT a wildflower)
Here are some pictures of Texas Plantain (also known as White Man's Foot) to compare with the pictures of Goldenrod above. While plantain can be useful (it has medicinal properties as a pain-killer) it can take over if you let it grow un-restrained. Oh, yes...and here is my example A of that. These tiny plantain plants are going crazy in a bare spot in my yard left by last years drought and a previous infestation of another weed. These new buds aren't visibly hairy like the older plants. The edges of the leaves start out smooth.
Later the leaves devolop hairs and jagged edges.
And eventually it will grow large seed spikes.
The picture above is by Calindarabus, who not only has great photos of tons of plants on Flickr, but includes info about the plant with each picture!