1. Excavate the top 4-6 ins layer of dirt and fill back up with new topsoil of good quality. 1 m- k, v! m6 h9 @' N% q$ F2 H) e2. Reduce the use of chemical fertilizer and use organic one instead.
: r+ R$ P" T6 O1 R# r
I should tell a bobcat is required if you wanna do the whole front/back yard OR just spot-excavation (dig a bigger and deeper than normal hole, dump the old dirt and back fill w/ good topsoil when you want to plant a new tree) if you gonna do the job yourself.