CLT49er said:
How far past the drip line do green giants roots spread?
Not to be a smart-*ss but, as far as they need to go for water and nutrients. How far below (downhill from) the trunks (uphill) will you be excavating?
CLT49er said:
Wondering if I can excavate out the hill within 2 feet of the drip line.
2-feet out from underneath the widest reach of the side branch tips may be considered close but, if you planted them 4 years ago assuming they've been established "only" 3 years your likely not going to encounter any "arterial" (transmission) roots but rather "capillary" and the finer "hairlike" feeders ...
CLT49er said:
Anything I can do to help the trees recover for the roots I inevitably will damage?
Absotively:
1) Consistent split app release feed as far ahead of shock event as possible (Nutrition for plants is preventative more than curative*) - allow plants to strengthen, enhance immune systems and store energy BEFORE shock event;
2) Keep plant hydrated (I would trickle irrigate the uphill side of the trees enough to keep the plant as close to homeostasis as possible during the excavation but obviously not to the point your creating mud on the downhill side where you'll be working)
3) Keep the exposed roots as moist as possible. I've had great success protecting adjacent trees roots when repouring driveway and sidewalk slabs by using a hose-end sprayer to mist the exposed roots (again, not creating a mud pit) followed by plastic sheeting laid down and held down with stones, bricks or landscape staples or spike as soon as I'm done digging for the day (and by that I mean ASAP - before I even start my cleanup for the day!)
4) Consider Foliar app.s AND Root Drenches by investing in either Phyton 27 or THE BEST anti-bacterial / anti-fungal (get out Yer wallet!) Phyton 35 and liberally spraying the foliage down and doing deliberative root drenches with dilutions according to label instructions a month or at least several weeks ahead of, immediately after and then a third a month after (*-curative) the shock event.
Your biggest enemies are (in order of occurrence): dehydration of exposed roots and fungal / bacterial infection via exposed roots followed by weakened immune system and susceptibility of the entire plant ....
If you REALLY want to ensure success (even if you go w Phyton 27 and not 35) procure ahead of time and have on hand SUFFICIENT AMOUNTS of BONE MEAL to sprinkle and mix into the soil closest to exposed roots as you backfill. Bonemeal is my own "secret ingredient" when planting or esp. transplanting shrubs! :thumbup:
CLT49er said:
Is there a better time of year to limit the stress or damage I may cause? Thanks!
The worst time to do this would be Spring into summer and best time would be Fall so, if you embark now it's not as ideal as waiting 10 or 11 months but it's a whole heckuva lot better than putting it off til March.
Below freezing can dehydrate exposed roots as much as summer heat (and unlike warmer temps really freezing temps obviate the advantages of the overnights plastic sheeting) but, considering you're an hour south by southeast of where I'm at (low to mid 20's overnight here this time next week! :shock: ) I'd have no compunction about doing your excavation as soon as possible now (as far ahead of the Jan / Feb "real winter" for CLT, as possible.
And of course, feed and monitor the trees like "post-op recovery patients" next Mar through July ...