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davidrt28

quick damage report on UDel arboretum

davidrt28 (zone 7)
10 years ago

I could post a few pics, but my cheapo smartphone's camera is so bad it hardly seems worth it. They hit 3F though I suspect were overall a little milder than my garden because of a miniscule heat island of the university, and the fact that many of the plants have protection of large building walls. I'll just do a quick run down:

Daphniphyllum macropodum - their various trees were fine, and are in fact self seeding in and around the walled garden that houses most of the subtropicals. The seedlings are fine!
OTOH D. humile looks a bit injured, confirming the tendancy of nurseries to rate it zone a bit less hardy.

Edgeworthia was already blooming...mine is probably still a week out, which is a month later than usual!

Mahonia gracilipes - looks dead just like mine
other Mahonias mostly of the X media persuasion - some minor burning but ok, as is my F2 X media seedling

Persea palustris - completely undamaged, which makes it all the more tragic they are being killed by a pathogen

Schima argentea - surprised me by still having some green leaves...I'm really looking forward to the X Schimlinia being released.

Prunus laurocerasus, various cultivars...fine

Ilex latifolia - moderate foliar burning, all other hollies including some you might worry about like X koehneana, X aquipernyi, vomitoria, are fine

Quercus virginiana - foliage almost completely burned but twigs probably ok

Quercus mysinifolia - totally undamaged, confirming how much hardier it is

Cleyera of commerce...fine...even less than the minor burning on mine, but it was protected from morning sun unlike mine

Magnolia yuyuanensis - mostly ok; some other rare Magnolias that were harder to find name tags on were more damaged, like a 'figo'

Magnolia 'Little Gem' (not labelled but I am almost sure) - quite burned, my 'Kay Parris' is almost completely undamaged and is obviously hardier

I'm sure I'm forgetting something...I was in a hurry and got sick of unlocking my phone to take pictures...might think of something else later. Oh one more thing, as is the case at the NCSU arboretum, the dry bed of desert plants mostly looked great, which is interesting considering how we had so much cold combined with snow.

This post was edited by davidrt28 on Thu, Dec 18, 14 at 7:26

Comments (29)

  • Dave in NoVA • N. Virginia • zone 7A
    10 years ago

    Great report. Thanks!

    In my backyard, my list of damaged plants include:

    Camellia japonica -- most varieties have fried buds. I only expect some blooms on RL Wheeler, Jerrry Hill, Bette Sette, perhaps a few others. Too early to tell though. Many that got any winter sun have scorched leaves.

    Daphniphyllum macropodum looks pretty good.

    Q. myrsinifolia in the backyard has many scorched leaves. The one in front yard with better wind protection looks fairly good.

    Q. virginiana have many scorched leaves, but twigs look ok,

    Q. phillyraeoides leaves are 30% bronzed. Twigs seem to be OK.

    Distyllium myricoides -- totally fried, but some twigs look good. I'll yank this plant. I'd say zone 8 or 7B in protected spot.

    Distyllium x 'Blue Jade' somewhat hardier but still a lot of scorched leaves.

    Citrumelo -- probably died back several feet (at best).

    Loquat - totally fried leaves, but may be twigs are oK, too soon to tell.

    Many loropetalum look fried to ground with exception of Zhu Zhou Fuschia.

    Little Gem, Teddy Bear magnolias look pretty good.

    Indian Hawthorn - all leaves fried. Will probably yank these.

    Gardenia Frostproof - fried but not sure how far down.

    Trachycarpus fortunei. Too early to tell how bad damage is . All fronds are fried. Will spears recover? Who knows?

    Needle palms -- spear damage on most. But one on protected south side looks pristine.

    Sycopsis sinensis, leaves fried, but twigs look OK.

    Dendropanax trifidus -- looks amazingly green.

    Yaupons -- 'Hoskin's Shadow' and weaping yaupon look pretty good.

    Aucubas got some leaf scorch in sun. Those in shade look look good.

    All hollies look pretty good with exception of the late summer growth on some varieties -- which got burnt -- (cassine hybrids, latifolia hybrid, integra hybrids). All Koehnes look good, but here are very well established plants. 'Lassie' is particularly hardy.

    Prunus lusitanica looks very good. I don't see any damage with exception of just a few bronzed leaves on the south side.

    Prunus caroliniana -- 20% scorched leaves in dappled shade.

    Chindo viburnum. Some scorched leaves from late summer growth. More damage to younger plants than older, established plants.

    Ligustrum japonicum - 50% damaged leaves at least. No doubt this will recover.

    Pot-planted Lithocarpus henryii with some overturned pot protection during cold spells. Flawless. Same with Trochodendron araleoides.

    Probably more damage will show up as temps warm.

    That's all I can think of at the moment.

    This post was edited by dave_in_nova on Tue, Apr 1, 14 at 9:46

  • davidrt28 (zone 7)
    Original Author
    10 years ago

    Thanks for your report dave.
    I forgot to mention regular camellias. They are mostly ok, I didn't note the cultivars but I think they are the typical hardier ones. But like I said they are all wind and morning sun protected. The odd species are in the less well kept north walled garden - the one closer to the campus. Funny enough a camellia oleifera, which is supposed to be the hardiest of all, was looking really bad. I wonder if the plant was already in decline.

    "Many loropetalum look fried to ground with exception of Zhu Zhou Fuschia. "
    Yeah my Zhou Zhou is ok, too, although I have no others to compare

    I have an Ilex 'Hoskins' which is very slightly burnt, but seeing that the plain weeping one was fine at Udel, I'd rather have that in my garden (surely one of the only plants where the weeping cultivar is more common than the regular one). It's kind of a boring plant if not for the weeping habit.

    Also forgot to mention I'm sure I saw a Cathaya in the arboretum last year, but I could not find it again! Maybe I did not look hard enough, or maybe they moved it. I'm sure it would have been fine.

  • davidrt28 (zone 7)
    Original Author
    10 years ago

    Oh and btw by OK with camellias, I mean foliar hardiness. Of course they probably mostly had their buds blasted, which is why I was impressed by that species.
    I think all my garden's Camellias had their buds ruined and don't expect to see any of them bloom.

    Too bad about Distylium, I had just bought one last year but had not planted it out yet.

    BTW: 11th coolest March in Baltimore, since the 1870s.

    This post was edited by davidrt28 on Tue, Apr 1, 14 at 23:20

  • Dave in NoVA • N. Virginia • zone 7A
    10 years ago

    The Distylium myricoides species is fried, but lower foliage (perhaps under snow?) is still green.

    I just ordered Distylium racemosum to see if it's hardier than D. myricoides. It may just be.

    Dirr used these two species to create his hybrids which he claims are hardy to 6b. Doubtful, as my Blue Cascade is showing a lot of damage.

    'Vintage Jade' is just now becoming available in our nurseries, so perhaps that one inherited a bit more cold-hardiness. Not really interested in 'Emerald Heights'.

  • sam_md
    10 years ago

    I spent the entire day Saturday at the Nat'l Arboretum. I have no pics because it came down in buckets the whole time. I did notice the following:
    -trachycarpus sp near the admin bldg, dead
    -laurus nobilis hedge nr herb garden dead
    -old specimen of laurus nobilis in herb garden damaged
    -loropetalum espaliers on admin bldg, brown foliage only
    -Persea sp in herb garden healthy & green. It is worth noting that Laurel Wilt disease has not reached the mid-Atlantic yet, hope it never gets here.
    I do have a large Camellia jap.Leucantha X Variety Z which is going by the name 'Anacostia' which has come through in flying colors.

  • davidrt28 (zone 7)
    Original Author
    10 years ago

    Thanks Sam. I wonder if any Trachys north of Williamsburg, VA, will have survived this winter.

    One more I forgot. Their huge Osmanthus X fortunei was undamaged. Makes me glad I just picked one up at Camforest, now I just need to find a place for something that can get that big.

    This post was edited by davidrt28 on Wed, Apr 2, 14 at 23:35

  • hairmetal4ever
    10 years ago

    I'm starting to think Quercus mysinifolia might be OK in a GOOD zone 6b location even from what I've been reading.

    I know one died in Howard County after -16F, but I don't know the exposure, etc. I'm zone 7a here, but with something like that (or even some other evergreen oaks), I'd almost want to do some trial run of a bunch of seedlings to select the hardiest ones over the years and clone the ones that survive the longest.

  • hairmetal4ever
    10 years ago

    Dave - does Citrumelo produce any sort of worthwhile fruit?

  • davidrt28 (zone 7)
    Original Author
    10 years ago

    "I know one died in Howard County after -16F,"

    That was based on what the nursery owner you spoke to out there said right? I'm worried I misspoke myself at some point...?

    FWIW several Lithocarpus henryi did survive that in Howard Co. It may be the hardiest evergreen Fagaceae of all. Mine here is in a very exposed site and laughed off this winter, even the parts above snow cover.
    In any case, I can imagine it would have killed a Q. myrsinifolia, because mine in western Fairfax County was about 8' tall, almost 1" caliper, but was killed to the ground by roughly -8F in 1994. I agree in a sheltered spot it might be a good choice for 6b, but not 6a. But don't forgot almost everything I listed at Udel is wind sheltered.

  • davidrt28 (zone 7)
    Original Author
    10 years ago

    "Quercus virginiana - foliage almost completely burned but twigs probably ok

    Quercus mysinifolia - totally undamaged, confirming how much hardier it is "

    NB the big picture here is, that very Q. virginiana down in upland SC, for example, might have been fine with a single night of 3F, followed by a rest of the winter at 40F or above. But even though Newark, DE, like me, only hit 3F, the incredible duration of the freeze just exhausted some plants' ability to cope.
    Hairmetal I agree your idea of trying a bunch of seedings is a good idea, if you have the room and the will to protect them from pests and weeds. I have a hedge of Ilex on my property away from the house, I've gotta go out there and untangle a bunch of Japanese Honeysuckle from it. Last year's wet summer meant that stuff must have been growing a foot a day.

  • hairmetal4ever
    10 years ago

    I think freezing of the soil has a lot to do with it.

  • Dave in NoVA • N. Virginia • zone 7A
    10 years ago

    hairmetal4ever: I may never know about citrumelo. My two plants died way back. Don't really know the extent of the damage yet.

    BTW, all of my osmanthuses are fine for the most part.

    I have O. americanus, O. 'Goshiki', O. x fortunei, O. x 'Burkwoodii'.

    Q. myrsinifolia had a rough time in the backyard. Will lose 50% of leaves. Twigs look OK so far.

    One plant that did admirably this winter was Prunus lusitanica. And all photinias look good.

    My weeping yaupon has a branch here and there that has died from cold (I assume), or perhaps physical damage from ice. This one has had cold damage when younger. So I'd keep it protected the first winter.

    It looks now like I may get some blooms on the following camellias:

    Turnadot
    Betty Sette
    R.L. Wheeler
    Jerry Hill

    Oh, and Laurustinus 'Spring Boquet' is fried as well.

    Aucuba 'Sulphurea Marginata' that I ordered from an online nursery has some fried leaf edges. But all buds look good.

    My large Persea borbonia has at least 60% bronzed brown leaves. Never happened before.

    Sam: Did you get down to see how the Q. acuta and salicina trees fared?

    Encouraging about Lithocarpus.

  • hairmetal4ever
    10 years ago

    I may try an L. henryi. I have a few Q. fusiformis acorns and may try to get a hold of a few Q. myrsinifolia acorns or seedlings for kicks as well.

    My thought is among most trees, oaks included, there are going to be at least some variation in hardiness, not only varying by seed provenance, but even among the same seed lot. Over time, if I plant a few in a home-made "nursery bed" (until they reach a size where they must be transplanted) I can see how they look after a few winters. I might try some in those "root bags" to make them a bit easier to transplant.

    Of course, my luck would be that I'd get a couple strong, hardy survivors, then kill them when I tried moving them to a permanent spot.

    It would make me actually HOPE for a repeat of this winter, just so I can make a true evaluation.

  • sam_md
    9 years ago

    I spent a little time at the Nat'l Arboretum yesterday, the place was mobbed for a number of reasons. BTW its only open four days a week.
    Here is the needle palm in Asian Valley. As you can see, no problem.
    {{gwi:339422}}
    Here is one of the evergreen cornels which came through fine.
    {{gwi:339423}}
    No problem with live oaks.
    {{gwi:339425}}
    The camellias look mostly fine, some of the sasanquas show some damage but it is minor. Loropetalums are a little ratty but they should come back quickly.
    All the rosemary in the herb garden is history but it may come back from the roots.

  • hairmetal4ever
    9 years ago

    I wonder how cold it got at the National Arboretum? I'd imagine it runs somewhat colder than the Airport (DCA) but probably milder than I was up here in Howard County. Except for that one night where it was so windy that even right on the bay they hit low to mid single digits.

  • bengz6westmd
    9 years ago

    Sam, that needle palm is impressive after such a winter. Evergreen bamboo copses around here are badly burned.

    After inspection I've come up w/a bit more damage than I first thought. Victoria southern mag had a number of inner branches broken from snow/ice. Still, not serious -- it has alot of branches.

    More concerning is a Green Giant arb completely dead, while no others show any damage. It was about 15' tall. It is the first in line w/the prevailing wind. Still, I have no other explanation.

    Longleaf pines show burn, but only on the oldest needles, so mostly superficial. Pond pine got clobbered by snow/ice, so had to re-stake it upright.

    Tiny Nordmann fir planted last spring is badly burned & tips chewed off by deer. Hopefully it'll survive. Tiny Manchurian fir fared better. Concolor fir got deer-rubbed again last fall -- not much viable trunk left.

  • Dave in NoVA • N. Virginia • zone 7A
    9 years ago

    Update,

    Citrumelos are mostly dead. Probably they will resprout from way down, or roots, but not worth it. I'm going to remove.

    Numerous Chindo viburnums that we in sun were severly died back.

    Viburnum cinnamomifolia (7 feet tall!) is gone to the roots.

    Numerous loropetalums are died nearly to roots.

  • hairmetal4ever
    9 years ago

    We lost more in the shrub than tree arena.

    Had a 9 year old Rosemary (unsure the cultivar, it was a gift) that had grown into a rather gangly 4' wide shrub - dead to the roots.

    A dwarf Buddleia (unsure again, my wife bought it) died to the crown but is resprouting.

    The neighboring Ilex 'Nellie Stevens' hollies have a lot of leaf burn.

  • bengz6westmd
    9 years ago

    Sam, thinking maybe that needle palm was indoors over the winter & brought out recently?

  • sam_md
    9 years ago

    Hi Ben,
    Maybe my pic doesn't show it but the palm is really much too large to dig up. Actually its been growing in that spot happily for 46 years. See link.
    Here is a random C. japonica that came through well. Its worth noting that the Asian Valley is on a protected hillside.
    {{gwi:339426}}

    Here is a link that might be useful: Needle palm in Asian Valley

  • davidrt28 (zone 7)
    Original Author
    9 years ago

    "really much too large to dig up"

    With any conventional equipment. However there are giant tree spades, surely not owned by the USNA but available to them via contractors, that can move almost any eastern US tree. They can make rootballs 25 feet wide and 10 ft deep! But of course there's no reason to go to such expense. (although, interestingly, Kew has found that lifting and re-settling their mature trees can be beneficial for their health sometimes. They just lift them w/a giant tree spade, and set them back down in the same place. They used to have a webpage about it.) Years ago one of those companies had a web page showing how Lance Armstrong's landscape architect had used such tree spades to move massive mature Texas live oaks in front of his Austin-area (IIRC) mansion.

    Camellias have really impressed me in this winter, generally. It would seem - and I'm speaking in generalities about the hardier cultivars - as long as the temp. doesn't go below the 0F threshold, dormant camellias can survive quite a range of abuses. For example, my 'April Remembered' and 'Aida' bloomed this year; the 'Aida' rather profusely in fact. I was sure their buds were going to be killed. So far 'Aida' is my fav. camellia, which is interesting because it's a (should be?) less hardy X williamsii. But of course it was selected by Longwood as the hardiest X williamsii. Funny enough David Parks told me there was some reason that particular X williamsii cultivar doesn't grow well in central NC, but my mind was wondering and I can't remember exactly what he said was the issue! Camellia japonica 'Destiny' did lose all of its flower buds.

  • sam_md
    9 years ago

    But of course there's no reason to go to such expense. Exactly, there's no reason to move the needle palm. It's been growing there since before there was an Asian Valley. Also a respectable specimen in Monkey County's Brookside Gardens not far away.
    Maybe this time link opens up.

    Here is a link that might be useful: Needle Palm in Asian Valley

  • Dave in NoVA • N. Virginia • zone 7A
    9 years ago

    My large Needle protected from the worst winds has no damage at all. Ones that got more winter winds had spear pull.

    My Ilex latifolia (about 9 feet high) had no damage this year thankfully.

    Turns out the very top top of my Prunus lusitanica did die back about a foot or so.

    I did notice some damaged bark way down on a small unidentified holly (likely Ilex cassine hybrid). I don't know if the bark split was from cold weather or from voles and/or rabbits though. Hopefully it will heal.

  • poaky1
    9 years ago

    Sam Md, where did you get your plant labels and the stand that you apply the labels to? I have some tree labels, but the labels didn't stick to the stands that I used. Many are buried under mulch. I need to get more labels for my new transplants, but sturdy steel "stands" where I can apply my label tags, would be great.

  • davidrt28 (zone 7)
    Original Author
    9 years ago

    While someone else had bumped this thread recently: I got annoyed - after asking several important east coast rare plant nursery managers like David Parks of Camforest - about the mysterious whereabouts of X Schimlinia. Or should I say - lack of whereabouts. Nobody is aware of how to get it. So I asked the hybridizer himself, and he simply confirmed it has not be released. No explanation given at all. Mind you the cross was made about 10 years ago, published in an academic horticultural journal as having ornamental merit. Not something I'm going to lose sleep over, but rather odd. It's hard not to wonder if is a political calculation - I'm reminded of that poster here a couple years ago who used to rant about "sinophobia". I guess the native X native cross seems politically correct and has feel-good marketing potential, while the chinese X native cross, which would probably be superior, could undermine our sense of national horticultural unity. Or something. Luckily for us the Chinese have no such silly qualms, with, for example, their Taxodium X Taxodium hybrid becoming immensely popular there before Creech finally took the initiative to import it back into this country.

    I know where to find Schima and Franklinia trees in the Delaware Valley...and I know how to move pollen around, too. We'll see...or maybe the Chinese will hybridize their Gordonias (like the one posted here by jujujo...now called Polyspora) with Franklinia.

    This post was edited by davidrt28 on Thu, Jul 3, 14 at 13:47

  • davidrt28 (zone 7)
    Original Author
    9 years ago

    Just a few minor updates from another visit to the UDel arb.

    Mind you most of these plants are in a protected location, though I'm not sure it made a huge difference in the 2nd, highly advective freeze.

    Their V. awabuki 'Chindo' was killed to the ground, but was vigorously resprouting. Same with V. cinnamomifolia.

    The Distyllium myricoides was totally dead. However Distylium racemosum was resprouting.

    An Itea oldhamii was killed to the ground but resprouting. They had various other weird Iteas I'd never heard of, like I. duclouxsiana, which was too small to know whether it was newly planted or just survived under snow.

    Mahonia 'Charity' and 'Winter Sun' were no only unaffected by last winter's freeze, but in full bloom. I need to get one of those, I think mine runs a little too slow. They have an 'Arthur Menzies' but I don't like the gawky look of it, and it wasn't in bloom yet.

    Their live oak is mostly recovered, but still a little thin looking to me:

    {{gwi:2122027}}

    BTW, in talking with a professional PhD degreed horticultural researcher recently - not necessarily affiliated with Udel btw - a possible explanation for the (likely permanent) non-availability of the new X Schimlinia hybrid has come to my attention. It's profoundly idiotic...even beyond my heretofore comprehension of such things. It's worse than the mere reason of poltical correctedness I listed, but related. I'll leave it at that.

    This post was edited by davidrt28 on Tue, Dec 16, 14 at 17:44

  • hairmetal4ever
    9 years ago

    So do we get to hear the explanation? You can't just leave us hanging!

  • davidrt28 (zone 7)
    Original Author
    9 years ago

    hairmetal, did you get my private message?

  • davidrt28 (zone 7)
    Original Author
    8 years ago
    last modified: 8 years ago

    A few pics from last week.

    The big Persea palustris which was basically undamaged in the past severe winters.

    The small thing in front of it (to the left of the Sabal*) is the Schima argentea that I'd already mentioned. It looks like it was about 1" caliper before the first cold winter killed it back - you can see the old trunk that was lopped off. What I'd never noticed is that along the wall was another Schima, that looks to have recovered even better last summer from the damage of the prior winters.

    Surprisingly, this was labeled as Schima wallichii, which I thought was considered more tender than S. argentea. But it looks better than the S. argentea, perhaps becaause of the wall protection. (this wall is to the north of all of the plants)

    Next a Mahonia 'Soft Caresse'; I can't figure out whether this one is the one that's been there or a while and was severely damaged in the cold winters, or replanted. It sure looked dead after the first cold winter, so I think it's a replanting. In any case, it's apparently Mahonia 'Delicious Caresse' to the lop-eared rats, because they've almost eaten all of the leaves off.

    Finally this species Camellia, C. yuhsienensis that I mentioned in another thread. This was the earliest camellia blooming after the first cold winter. Likewise, it was now still blooming well, even though we'd had some cold spells by last week. It wasn't the only camellia blooming in the gardens though, something that looked like Camellia 'Korean Fire' was blooming. Small flowers but I certainly would make place is my garden for such a cold resistant camellia.

    * - yes you will notice to the right of the Sabal minor is a Butia! I have no idea what they are thinking in planting that. It already looks mostly dead after this mild (so far) winter.