Your infield may need attention.
This look often happens when your spring baseball season is over and your infield lays unused for the summer. The lack of regular maintenance techniques like nail dragging and the drag matting every day invites crabgrass to take over even the best maintained in fields.
Ways to Fix Your Field
There are a couple of different ways to remedy this problem.
Method 1
If you have access to a rototiller, adjust it so that the tines disturb only the top 1" of infield mix. Rototill the effected areas, hand rake out the vegetation, and then level with a home made leveling screed. (8' 4x4's screwed 3' apart and pull behind your tractor.)
If water is available, wet down the affected areas.
Method 2
The second way is to simply 'weed wack' the crabgrass right down to the mix. On our infields, the lawn maintenance crew is instructed to weekly inspect and weed wack the infield as necessary through the summer. This cuts down on the field prep for next spring.
Both ways work.
Best Field Prep Times
While we are on the subject of spring field prep, the best time to do it is in October or as soon as the fall ball season is over. That way all drainage, leveling and edging issues are taken care of before winter.
In the Philadelphia area,with the season starting the first week in March, February is no time to attempt to do this work. If you have questions or need support, don't hesitate to email or call me!