Well, I have more dogwood seedlings popping up in the elderberry, honeysuckle (yuck) and walnut grove. I'm gonna let them go and see what they turn out to be. The big fella here had a good summer. Fall is a bit lackluster. It has been VERY dry and unseasonally warm. The leaves look less dry than on an older Cornus florida in my yard but many have fallen off with less color.

I would go ahead and prune it, just to get it done. Optimal pruning time will be anytime between now and budbreak in the spring, so there's no particular rush except just to get it off your to-do list. If you're not familiar with how to prune, you might do a little web surfing, but it's not complicated. The depth of mulch can vary depending on what you used, but with products like fine bark chips or shredded mulch, 3" to 4" is usually about right. I usually thicken the layer a little more towards the outer limits of the mulched area. It's also a good idea to leave 1" to 2" of unmulched area right around the tree's trunk. This will keep the mulch from holding moisture up against the bark which can cause pest and disease problems and it discourages rodents from using the mulch as a cover while gnawing on your tree. Rake the mulch back from the trunk before you put your cage on, but wait for a warm (comfortable for you) day to fine tune your mulch.

lisa, a few suggestions. you might really benefit from a trip to ct. for Variegated Foliage nursery and Broken Arrow nursery. we have bought alot of unusual woody plant material from them (as well as from john, and tranquil lake nursery in rehoboth. )I am big into foliage colors so our arboretum gardens have alot of purple, blue, and yellow leaved plants. I do think that you will want to include ornamental grasses and sedums in your shrub border. Some of my fav shrubs that are not on your list: FAVORITE Z.5-HARDY DECIDUOUS SHRUBS- AND THEIR SPECIAL VALUE VIBURNUM SARGENTII ONONDAGA lg. Shrub, wonderful maroon bracts and maroon tinged spring foliage VIB PLICATUM VAR. TOMENTOSUM SHASTA layered branches,lg wh. flat flower heads and SHOSHONE (like small Shasta) VIB. SUMMER SNOWFLAKE blooms all summer, flat white flower heads V.DILITATUM ERIE and IROQUOIS V. PINK DAWN v. early small pink blooms CORNUS: all are large shrubs except the mini C. ALBA AUREO MARGINATA VARIEGATA- great bold med dk gn leaves w/ bold wide white edges CORNUS MIDWINTER FLAME stems coral to flame in winter; fall fol. Color warm yellow/suffused w/ coral CORNUS AUREA yellow summer foliage C. GOUTCHALTII med dk gn leaves w/ wide bold yellow edge CORNUS MINI VARIEG like alba aureo marg. var. but small- 2globe. CLERODENDRUM TRICHOTOMUM VARIEG. lg. shrub, lg. heart shaped med gn. leaves w/ clean yellow edge, stay on late in fall. Dies to ground and sprouts anew every yr. DAPHNE X BURKWOODII CAROL MACKIE small shrub, small dark gn lves w/ cream edge, sweet smelling spring pink bell flowers DEUTZIA GRACILIS NIKKO small compact shrub covered w/dainty white spring bells DEUTZIA AUREA- dainty yellow leaves keep their color ELEAGNUS UMBELLATA -lgshrub, silver foliage, can control size by pruning. FORSYTHIA x INTERMEDIA AUREA- small fountain of small bright yellow foliage. keeps yellow through season F. KUMSON - med.gn.foliage w/ strong white veining BERBERIS HELMONDS PILLAR - small ( to 4hx12"w) columnar , burgundy foliage B. RUBY GLOW - burgundy foliage med globe B. AUREA - medium, SLOW growing compact globe , brilliant yellow leaves COTINUS COGGYGRIA GRACE lg. Shrub, smoky blue- green- plum foliage C.COG. ROYAL PURPLE med to lg shrub, burg. foliage, likes dry, exc. drainage C. COG. AUREA yellow leaved, slow growing. PHILADELPHUS AUREA - med. size shrub, small yellow foliage until lime from mid july on. PHIL. DOUBLEFLOWER PRUNUS X CISTENA - med to lg shrub,small maroon leaves DISANTHUS CERCIDIFOLIUS -med to lg shrub .heart shaped leaves, wine red fall foliage CARYOPTERIS _DARK KNIGHT - small loose fountain of deep blue racemes_ BUDDLEIA ELLENS BLUE -med to lg shrub, good saturated blue/lav.flower wands BUDDLEIA DARK KNIGHT - dk. ppl. wands HYDRANGEA TOKYO DELIGHT flat pink flowers HYDRANGEA QUERCIFOLIA SNOWFLAKE flat dbl. blossom heads of wh. flow. w/ pale yell. centers HYDRANGEA KYUSHU - july/aug. blooming, loose conical white flower heads SYRINGA DAPPLED DAWN - med. to lg size, green foliage splashed w/yellow SYRINGA SENSATION - (flowers of dk.ppl.rimmed w/white) SINOCALYCANTHUS Hartledge Wine - new hybrid; 2-3" sweet smelling maroon dahlia-like flowers , long bloom time CALLICARPA PROFUSION - med to lg shrub,fall wands of small med ppl. berries CLEMATIS CORYLOPSIS SPICATA v early spring light yellow bell flower racemes VITEX AGNUS-CASTUS lg shrub, similar to buddleia in habit, blue blooms V.LATE(oct/nov); v.wonderful fragrant foliage. Dies to ground in winter and resprouts from base in spring. WEIGELA FLORIDA VARIEGATA lg shrub, med gn leaves w/ wide bright yellow edge WEIGELA FLORIDA MIDNIGHT WINE mini, varieg.burgundy foliage KERRIA VARIEGATA - small fountain of serrated green leaves w/ white edge NEILLIA SINENSIS -a fountain of coral flower racemes in e.june, delicate serrated leaves CHAENOMELIS -bright cup shaped salmon,orange or pink spring bloom HAEMAMELIS late winter small raggedy blooms- yellow to orange/red ILEX WINTER RED profuse red berries in fall/winter PHYSOCARPUS OPULIFOLIUS DIABLO (dk.ppl.leaves) and AUREA (yellow foliage) AESCULUS PAVIA lg shrub w/handsome 5 part leaves and large bright salmon flower panicles FAVORITE Z.5-HARDY EVERGREENS- (TO BE COMPLETED) CHAEMY.OBTUSA NANA LUTEA CH. PISIFERA SNOW CH. OBT.

If this was its first winter, then I suspect the culprit is cold damage. You are located in an area where Japanese maples are of borderline winter hardiness, you experienced what is the equivalent of a zone 4 winter this past season and Shishigashira is not considered to be as cold tolerant as some other JM's. Most authorities only list it to zone 6. I also have some concern about the planter box. In the last photo, it looks like the planter is resting on heavy duty landscape fabric and not in direct contact with the underlying soil. Is this why the tree was planted high? Not enough depth for the rootball? And no winter mulch? This definitely could have been a contributing factor. Need more details on the planter itself before suggesting whether replanting another tree makes sense.