Gardengal, Seriously, I don't get my info from Wikipedia which is probably the worst place on the net to get correct information. First of all, I have 5 Giant Sequoia, so I have studied about them from various sources for years. I also have been to California several times to see them and this was during the winter and early spring, not just thevsummer and I can assure many areas get flooded. Most people and photos you see are people that go during the summer (dry season) when the water level drops. There are huge giant sequoia growing smack in the middle of a creek in a gravel bed estimated over 1000 years old. The info I refrenced is from the website of the #1 grower of giant sequoias in the United States. For one, technically there is no sandy loam in the Sierra Nevada, it's alluvial granite. Second, the mature trees need thousands of gallons a water a day to survive, they are not getting that from JUST "moist soil", they have a massive source of water at all times. Third, they have a very shallow root system for the size of the trees, that means they get most of their water from the just above the soil to about 10 feet below. But your repeating info from a man (John Muir) that first wrote about Giant Sequoia before the 1920's that has been debunked long ago. This is an excerpt from the National Park Service today: "John Muir was perhaps the first writer to single out the role of soil moisture. He found that medium soil moisture is optimal for sequoia growth. The sequoia is never found in any valley exposed to the rush of floods, nor on any hillside so steep and unporous as to shed its soil and rain. It grows always where the deep sandy or loamy soil is capable of holding the winter moisture all the year, or where the rock is full of innumerable fissures and is shaded and cool and moist" (Wolfe 1938). Even though he failed to indicate the necessity of sunlight for seedling development, his assumptions are essentially correct, and many writers have repeated them in modified ways. Invariably, these modifications involve the effect of climatic differences, soil type, depth of organic layer, leaf litter, shading, etc. ***Recent investigations, curiously, do not bear out the belief that rich, deep soils are a necessity for sequoia growth. Observers have tended to compare forest soils to agricultural soils. While crop plants need nutritionally rich as well as moist soils, trees depend mainly upon available soil moisture. The grayish podzolic soils of the Sierra are less than impressive to the serious farmer. Furthermore, many people tend to grossly underestimate the complexity of soils. By and large, Sierran podzolic soils are relatively thin and not abundantly nutritious. With clay a minimal soil constituent, the total moisture-holding capacity of these soils is limited by the amount and distribution of precipitation, subsequent density of vegetation, temperature and relative humidity during the growing season, and the wetability factor of the soil. Sequoias show a strong tendency to favor drainageways where the requisite degree of moisture content is constant. Yet the drier slopes also support sequoia growth wherever the trees can become established (Wulff et al. 1911). Contrary to popular belief, then, soil depth and richness are clearly secondary to soil moisture availability. Sequoia distribution within groves strongly reflects its affinity for soil moisture; a crown that may weigh a ton or more seems to demand it. Muir (1911, 1912) was a proponent of the thought that sequoias created their own moist environment as he wrote below. "It is a mistake to suppose that water is the cause of the groves being there. On the contrary, the groves are the cause of the water being there. The roots of the Big Trees fill the ground forming a sponge which holds the water. The Big Tree is a tree of life, a never-failing spring all through the hot, rainless summer. For every grove cut down, a stream is dried up." Perhaps Muir failed to understand the magnitude of transpiration, i.e., the vegetation "pumping" soil moisture back into the atmosphere. It is true that forest vegetation regulates the yearly flow of water, thus modifying the distribution of runoff and moderating the extremes. Forest trees play an important role in cycling water from the ground back into the atmosphere. Removal of the transpirational pumps, namely, the trees, has often converted a dry forest into a swamp. The patterns of growth- and site-selectivity all bespeak the species' affinity for high soil moisture and reflect the effect of temperature and relative humidity perhaps more than does precipitation alone. The ratio of evaporation potential to precipitation as an environmental factor is important, and its recognition has produced the widespread belief that the sequoia grows best in protected locations where the average annual precipitation is from 45 to 60 inches (Schubert 1952). Rundel (1969) amplified this interpretation somewhat. He found that sequoia stands on northerly slopes have greater density than on slopes of other aspects, although the total number is generally less. It is perhaps perplexing that these trees, admittedly with an affinity for abundant soil moisture, are much more numerous on westerly and southwesterly slopes, which are potentially the drier ones because of the sun's more nearly direct rays. Thus, for example, relatively moist drainage bottoms and meadow margins, although small in their total acreage, support dense stands of sequoias. Even rocky slopes support some 3% of the total sequoia population in the Giant Forest. Contrary to the records of John Muir, large specimens are fairly common on slopes exceeding 30° and we find some on slopes approaching 45°. We conclude that, regardless of a grove's geographical position, this species favors avenues of surface or subsurface drainage. Although surface drainage patterns are obvious, subsurface drainage may be too obscure for visual identification. The Grizzly Giant in Yosemite's Mariposa Grove, a good example, grows on a low ridge which appears well drained, but an apparently abundant subsurface flow of soil water is undoubtedly a major reason for the tree's great size. Evaporation potential is partly a function of temperature. Since temperature decreases with increasing latitude, average temperatures in the north are the same as at higher elevations in the south. Thus, the mean altitude of sequoia groves in the Kaweah Basin to the south is 6600 ft, whereas it is 5400 ft in the northernmost grove. In the northern groves sequoias are found mostly on south-facing slopes; in the southernmost, on north-facing ones. Altitude and direction of slope, then, indirectly reduce water loss from the trees while maintaining an optimum temperature regime for growth. The stream drainage channels are also channels of cold air drainage, especially if they descend from high mountain peaks, so that the value of available moisture must be pitted against the limitations of winter survival when temperatures may drop to sub-survival values. The same drainage channels, however, transport cones and seeds that are carried downslope where grove extensions form long, narrow fingers and occasional detached outliers. In the Mariposa Grove, flooding, not too many years ago, carried seeds along a tributary of Rattlesnake Creek, and today there are numerous thriving young sequoias mostly at high flood level on either side of the creek. No parent trees grow above them, although some are so close to the drainage divide that chickarees might have carried the cones into the other drainage basin to eat them. Perhaps the best-known and most classical grove extension is along the South Fork of the Kaweah River below the Garfield Grove. A dozen sequoias line the river bank at elevations as low as 2800 ft��"one specimen growing on a gravel bar in the river channel, a most unlikely site (Fig. 29). The altitude is the lowest known in the world for a naturally seeded giant sequoia. An increment boring indicates that this tree was seeded in the middle 1880s, when a torrential flood also floated huge sequoia logs through the town of Visalia some 40 miles to the west in the San Joaquin Valley." I can go on and on with info, but as they point out with this statement: "We conclude that, regardless of a grove's geographical position, this species favors avenues of surface or subsurface drainage. Although surface drainage patterns are obvious, subsurface drainage may be too obscure for visual identification". Surface drainage is from water draining off the surface from rain, snow or flooding from creeks, rivers etc.. Sub surface is obviously from springs, cracks and fissures pumping water upward or a high water table. from the original poster: "In the dry of summer the water table drops to 2' down. Rest of year it's about a foot or less below grade. After a good rainstorm there will be 2-3" puddles that last for days even weeks." I see no indication of swampy area here. Puddles does not mean swamp and after a good rain storm in the Giant Sequoia groves you will see puddles that last for a awhile. I do not see any indication the water in the area is from run off or a collection point. She indicates she is in the mountains, that's exactly the same growing conditions as a Giant Sequoia. In addition, her summer water table is fairly typical of a sequoia grove water table that's not on a mountainside.

" I wonder how one would do in pure muck soil where taxodium grow, if inland enough where saltwater flooding isn't a problem." Not well! It would last about a week in summer before the root rots would take it out! In the rest of the southeast where they do grow, they definitely only grow on well drained soils. I have had one die from root rot. In spite of being hexaploid, they are not invincible. FWIW, there's a 'trick' about the PNW - coastal CA climate. I saw rhododendrons almost in the bottom of swales at the old Greer Gardens in Eugene, OR.* You would NEVER see them growing somewhere like that in PA, NJ, or MD. But...the time plants like rhodies and redwood are most susceptible to root rot organisms is in the summer. That's when most of those disease organisms grow best...at temps >= 15C. I see redwoods in the native environs growing in soil that appears year round damp, but guess what? It's only going to be inundated with water, during California's wet winters! Likewise with the rhodies that would experience wet (but not underwater, mind you) soil conditions at Greer...only in winter! There's just NO WAY for Eugene to have 3" of hot wet rain in late July, on a single day, as we can have! (or, now that I think about it, at Sonoma Horticultural Nursery, which is called something else these days, the same is true. Although Polo did put some rhodies on the lowest plains of his property in impromptu little raised beds. That might be necessary because he was so mild in winter, root rot organisms could still grow well during the wet season.) Now that a nursery has supposedly grafted Sequoia onto Metasequoia, maybe people in the southeast can plant them in poorly drained soils with abandon. We'll see. * - although, TBH, it wasn't much to see and not even as nice as the peak of NJ Rarefind around the time Hank died in 2009, I'm glad I got to see it in 2011 and meet the famous Mr. Greer. Greer might have had rarer, more tender cultivars in zone 8a, but Rarefind had just more plants, and better displayed, period, in their 6b garden.

"One study showed about 6% of the water in the leaves were from fog in some trees. " Right, so the notion that they "need" this source of moisture is romanticized pseudoscience. Just because something happens, doesn't mean that this is the cause of everything else that happens. If they could merely subsist on the fog, then why haven't they reached 600', 700', or 800'? In fact since their range goes up to 2500', the right magical fog clearly exists at that altitude, too, and trees at ground level should be able to reach 2800' at least! LOL. Any moisture loving plant can grow better, or faster in a moist climate. Duh on that. But to specifically say that these trees can only reach that height because the fog is the _only _reason they can reach that height, is the height of absurdity! If you plotted standard deviations of soil moisture and drought with tree heights around the world - guess what you'd find? The places with plentiful, consistent soil moisture and rainfall are going to have the taller trees...and the places without tropical storms the really tallest trees. The sugi of Japan top out a bit above 200' - as would the redwoods of California if they had monsoon thunderstorms and typhoons to deal with. And guess what happens in climates with very consistant moisture that don't have the tropical waves and ridging/troughing - well they are maritime climates and by definition will have fog. The fog is associative, not causative, for the tall redwood trees. The only competition is Eucalyptus regnans, which, guess what, comes from moderately elevated areas with consistent rainfall and atmospheric moisture. (my brief google research suggests Tasmania is not known for thick summer fogs, but it is certainly wet, and w/o California's summer dry season. In fact, its native range _doesn't_ include the NW coast which is probably the foggiest part of Tasmania.) And guess what their upper limit is in spite of being morphologically completely different from conifers? About 400 ft! The fact is you won't find many other places in the world that have soil moisture as consistent as redwood coast, and the right temperature parameters, and the right absence of storms, lightning and high winds. But if you did, they could also reach 400' there. This post was edited by davidrt28 on Fri, Jan 2, 15 at 23:59

Well some of the Highclere hollies are either thornless or mature to being thornless, so you can't hold that against them. I feel like these must be common in many English public spaces? So I'm surprised you are asking me about them and not vice versa! Your charming little churchyards, city parks, or even urban roadway verges always seem to be brimming with attractive plants, often BLEs, compared to our weed strewn American equivalents. In fact thinking about the churchyard in Rye has made me think of the Sorbus tree there...and I wonder if perhaps the deciduous plant in berry overdrive (clearly, turned up to 11) in the picture above is some fecund local species of Sorbus. Of course it helps (or hurts...) that even some of your invasive weeds are gorgeous. I understand why those in the UK want to get rid of Balsam there...but good heavens. I have fond memories of seeing those along the Leith in Edinburgh. They are absolutely beautiful. (the Himalayan I. glandulifera...which probably wouldn't survive our muggy summer nights.) BTW your point in the pear thread about us having "land to waste" while western Europe does not, is well taken. It was very amusing for me to see that in northern Italy or Switzerland, little patches of land in the space formed by railroad wyes* - no more than an acre or two - were used for farming. You wouldn't see something like that in the US, ever. What's even more remarkable in the US is how vast swaths once used for farming, are no longer even needed, and reverted to un-managed woodlands. Much of New England, and much closer to me, the entire Elk Neck Peninsula. The yield for standard stuff like corn just couldn't compete with Midwestern farmers and their richer soils. I don't think something like that has ever happened in western Europe, and quite to the contrary, the Dutch turned a lot of a non-arable land into arable land. (Or just seawater - the ultimate non-arable land!) * - apparently, triangular junctions of railways in British English LOL