Go to the library and get a book on garden soil, see if they can get
"Teaming with Microbes" by Jeff Lowenfels

No, no, buy a copy! Sorry, I wrote it! Either way, if you get a
first printing there is a mistake on page 41/42 in which the
definition of pH is reversed. Now that really makes you want to read
it, right? You will love it. It is published in England and New
Zealand as well as USA and Amazon.com has a great price. You really
need to understand the soil food web in order to make educated
decisions about what to do....even if you decide to go chemical,
rototill and plant invasives....none of which I hope you will do!

Cheers and happy reading,

Jeff Lowenfels
Teaming WIth Microbes: A Gardener's Guide to the Soil Food Web.