Tree or Weed Identification

Question

About 7 weeks ago, my lawn exploded with an alien plant that we cannot identify. I thought it was a sucker root from trees which we have had removed, but the leaves are not the same. A plant expert from a local park thought it was a weed with an underground root system. It has small, roundish-oval leaves that are slightly ripply (not a flat leaf, in other words), no teeth on the edges, no point at the end or nodes and has a long white root – it grows singly or in bunches of 30 or more. It’s coming up all over my yard. I’ve never had it before. They are easy to pull out, relatively, unless you get a huge clump. I’ve probably pulled out over 1, 000 of them in the last 6 weeks.

They are in flower beds and the lawn on the south side of my house, in an area about 40′ long and 9′ wide. They are even coming up between the cement patio slab that butts up against the house (very little space). Some of the roots are 5″ long even though the green part is only 1-1/2″ long when I pull them and are quite thick. Any ideas of what this might be? Southern California – we had a lot of rain last winter but this area does not get run-off.

Answer 1

If you could send a picture this could help.

If does sound as if a seed from another tree may have blown into your yard.
Removing them quickly is the key.

https://www.gardeningknowhow.com/ornamental/trees/tgen/weed-trees.htm