Let me first say, there are a LOT of little yellow flowers with green leaves. We will focus on plants in 2 different families, which are larger groupings of plants sharing some similar characteristics. Although many bioregions will differ in all their little yellow flowers I am going to differentiate between a few that are common in my bioregion of Central Texas. We will start with Wild Mustard in the Mustard Family, and then go on to another Family, the Asteraceae and look at the difference between Dandelion, Sow Thistle, Prickly Lettuce, and Texas False Dandelion.
In our cooler, moister times of the year,(especially early spring), one Genus of plants that can get mixed up in this mess of Green and Yellow are our Brassicas, or Wild Mustards. See Mustard Family characteristics here. Edible Mustards/Brassicas are weeds, and show preference to disturbance. Edible varieties(as in palatable) have yellow flowers with big wavy, lobed leaves in our bioregion. One way to know you are looking at a Mustard is by taking a look at the flowers. The Family’s Old name was Cruciferae(before being renamed Brassicaceae), meaning Cross. The flowers in the plant family are small–like less than an inch in diameter in the shape of an X or H. Its important to remember that they aren’t picky about where they come up, and they tend to clean the soil around them up a bit, a process known as bioremediation. What that means for you is that its a good foraging plant as long as its living in a place in which you know the history of the land. I have seen it flourish along the sides of roads, in sewage effluent(as my survivalist friend insisted on picking them and eating the leaves before she examined the area) and many other disturbed grounds. Another Mustard family characteristic is the hot, pungeant, bite that you taste if you put the plant in your mouth—if you are certain of your id and know the history of the land.
The Asteraceae (formerly Compositae) Family, has so many little yellow flowers that botanists used DYC (or Damn Yellow Composites) to describe many of the little yellow flowers that look similar in this family. The other plants that usually get mixed up together in my bioregion are what a lot of folks would at first glance call a “Dandelion”. All of the following plants I am discussing are in the family Asteraceae Family , formerly Compositae that I mentioned at the beginning of this article. This family is a little tricky for the beginning botanist so read more about it here
. The most important thing to remember about this family is what look to be flowers are actually many flowers packed into heads–consisting of disc and /or ray flowers.
These little yellow flower heads come out around the same times of the year and can get tricky to figure out. Lets start with a true, non-Native European weed Dandelion, or Taraxacum officinale
. What appear to be flowers are actually “heads” of flowers which can get to be about 2 inches in diameter in our bioregion. Dandelion is a well known cooling medicinal and edible plant used as both a nutritive herb and for its action upon the kidneys and liver. All parts of it have a long history of use. It is a non-native weedy European herb that flourishes in the cooler months, the flower heads appearing at ground level, then shooting slowly upwards about 6 inches, usually around February in Central Texas. One of the first indications that you have found a Dandelion is to look down and see if there is a basal rosette of leaves, meaning that the leaves are arranged in a clear, circular pattern when looking down from above on the ground. Dandelions will not grow very tall in Central Texas. The leaves remain on the ground in this circle, or “whorl” coming directly up from the root and have toothed edges, where the plant gets its name. Another defining characteristic of a Dandelion as opposed to other Asteraceae, Composites, with yellow flowers and green leaves is that the flower head shoots up from the ground as a single or solitary inflorescence, meaning there will only be 1 flowering head per stalk. If there are multiple flower heads along the stalk, it is not a Dandelion.
A common plant to get mixed up and called a Dandelion in Central Texas is the non-Native and Weedy Sow Thistle, or Sonchus oleraceus.
I have included a picture above of another Sow Thistle species to show the basic difference between the two plants. As you can see Sow Thistle has multiple flower heads, usually smaller than Dandelions, that can appear on the thick, prickly, juicy, hollow stal
k(where it gets its name), which may also have additional leaves climbing and clasping around the stem
as it grows that are dark green sometimes almost purplish tinged. Dandelions do not have additional flowers or leaves on their flowering stalk. They have a single head, thats it. Sow Thistle is also quite prickly and likes to work its way all over lawns and gardens. If you pull a leaf off–ouch–, you will see its very juicy and has some white latex, or exudate. It can grow quite tall, unlike Dandelion–sometimes up to 3 feet.
The deep tap roots, prickly leaves, and huge basal rosettes of leaves can be competitive and disruptive in gardens(they also consume a lot of nitrogen and space), but keep in mind that these plants hold soil in place so that when we get large downpours we don’t lose our soil into our waterways. Sow Thistle is edible…but it is very bitter and may need some help to be palatable. It has a lot of micronutrients, like dandelion leaves. Sow Thistle has also been used medicinally, and is in fact somewhat similiar to dandelion in its uses. I found a pretty interesting study on a species of Sow thistle exploring its antioxidant and antimicrobial activity here
Another plant in the Asteraceae family that can be hard to distinguish is Prickly Lettuce, or Latuca serriola. Prickly lettuce usually blooms a month or two later in Central Texas, and can hold out later(many plants are beat back from the sun). Like the other two plants I mentioned, Sow thistle and Dandelion, it also, it has basal leaves in a rosette, but its rosette can be a little fluffier and much less prickly that Sow Thistle. The leaves, like Sow Thistle will clasp around and grow up these tall stems but the leaves are smaller than Sow thistle and more linear, almost more delicate as well as being a paler green. One of the defining characteristics of Wild Lettuce is the spine that can be seen along the midrib of the underside of the toothed leaves. Wild Lettuce is edible like the others, but again, palatable?–your choice. In my practice I use it more as a medicinal than an edible, and contains a white latex when a leaf is broken open, thought to be responsible for some of its calming medicinal action. Interesting that Sow Thistle has some latex, but I do not know the constituent profile of it compared to Wild Lettuce. Prickly Lettuce can get quite tall, when given enough water and in the wild I have seen it grow up to 6 feet tall in drainage ditches. Usually the plant stays around 2-3 feet in yards. It has multiple flowers growing up its stalks and the flower heads are usually smaller than Sow Thistle–usually under an inch in diameter.
Lastly, we come to Texas Dandelion or False Dandelion… (as if there arent enough), the Native Phyrrhopappus multicaulis
et al.(and other species) This plant has a couple of differing characteristics from Dandelion. Like the others you could have a hard time with distinguishing, its leaves can be basal and travel up its stems. Remember, Dandelion leaves stay in a basal rosette on the ground and will never travel up any stems. If you look underneath the False Dandelion, you will see reddish stripes extending from its pappus–creating elongated red sepals. The Native Plant Information network says the heads of flowers close at noon, but they also incorrectly say that the heads are solitary. False Dandelions can have more than one head of flowers borne along the stem. False Dandelion, like Dandelion has a basal rosette, and its rosette is more delicate than Sow Thistle or Prickly Lettuce, though still similar in appearance to Dandelion. False Dandelion has deeply divided leaves but not toothed like Dandelions. One big difference I have found is the False Dandelion, native is found in very different PLACES and TIMES flowering than Dandelion, a nonnative weed. False Dandelion can be found in our open fields/prairies in spring into early summer, whereas Dandelions are found in the city, in lawns and roadsides in late winter. European Dandelion requires cooler moister weather. Another defining characteristic is the flowerhead differs between the species. As mentioned before, the heads of flower contain disc and or ray flowers. In Dandelions the ray flowers overlap all the way to the center–there are no disc flowers see this link
and in the Native False Texas Dandelion, there are visible disc and ray flowers see here
I hope this little overview helps you to make sense of some of the common little yellow flowers out in Late Winter and Early Spring in Central Texas.
Please post any good photos here to illustrate the differences even more, or any other findings you have.
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