Goat head weed, or puncture vine, is a common weed in our area.  It prefers bare or disturbed soils and is also common at the edges of sparse or unhealthy lawns.  You are doing the right thing now by preventing the weeds from going to seed and collecting the seeds that you can see.  One effective way to remove the seeds is to drag old pieces of carpet or burlap across the soil to snag the seeds. Unfortunately, this will not catch the seeds that are beneath the surface of the soil.  The seeds can remain dormant in the soil for up to twenty years.   The weeds will be easier to control once your lawn is established because this weed is not a good competitor in healthy, dense lawns.

Hand pull any puncture vine that you see in your new lawn until the lawn is well-established.  Once the lawn is old enough, you can use a pre-emergent herbicide to prevent the weed seeds from germinating.  You cannot use a pre-emergent herbicide on the lawn before then because it will interfere with the germination and establishment of you grass seeds.  Check the label on the herbicide to see how long you need to wait after planting.  Maintaining a dense, healthy lawn will reduce the number of weed seeds that germinate.  Also avoid mowing the lawn short.  A tall lawn will shade the soil and reduce the number of seed that germinate, too.  Monitor the edges of the lawn, once established, and remove any seedlings that germinate in the exposed soil at the edge of the lawn.

As for varieties of grass that will do well in part shade and high traffic, I recommend that you look for any shade tolerant mix.  Fescue, rye grass and bluegrass all have moderate shade tolerance.  Remember that shaded lawns need less water.  Overwatering these areas will make them less tolerant of traffic.  If you can, make adjustments to your irrigation system before you plant so that the shaded areas can be watered separately from the areas in full sun.  Also, keep the dogs off of the lawn until it is thick and healthy.

I hope this has been helpful.  Feel free to call our office if you have any other questions.  801-851-8462

Meredith Seaver
Horticulture Assistant
Utah County Extension