Sunday, January 31, 2010

Planetrees & Sycamores

A family of trees with globe shape fruits that is native to North America, Europe and Asia. They are widely used as shade trees, are wind sturdy and are tolorant of compacted soils and air pollution. They prefer moist, deep, fertile soil in full sun. Pruning is preferred to train to a single trunk and limb up when young.

* photos taken on July 25 2015 @ Niagara-on-the-Lake, Ontario

Platanus x acerifolia ( London Plane )
Also called Platanus x hispanica; it grows with a large pyramidal later becoming rounded form. Very fast growing it can reach 60 feet in 20 years and eventually 100 feet. However on ideal sites this tree is extremely vigorous to extreme sizes. 133 x 66 feet has been known for 20 years and the largest London Plane ever recorded in Europe reach up to 190 feet in height; 80 feet in width and 13 feet in trunk diameter. Some additional records include: 100 years - trunk diameter of 6.5 feet; 143 years - trunk diameter of 10 feet. The London Plane is actually not native to Europe despite being widely planted for centuries. It is actually the hybrid of the American Sycamore ( Platanus occidentalis ) and the Oriental Plane ( Platanus orientalis ).
The leaves are 5 lobed ( deeper lobed than American Sycamore but less than Oriental Plane ) and bright green. However in humid climates of the Eastern U.S.; this tree is very prone to leaf diseases such as anthracnose and mildew and is very often either ugly brown or defoliated by late summer. I personally find this irritating, IT IS UGLY!!! There is no excuse for it either since there are many better trees including some new disease resistant cultivars of this one such as 'Columbia', 'Metroshade' & 'Yarwood'
The fruits are small aggregate balls that are often produced in pairs.
The London Plane though often overplanted; is still a great urban tree since it really is tolerant of heat, drought and pollution. Hardy from zone 3 to 9.
The cultivars root easily from softwood or hardwood cuttings under mist in about 6 weeks. The hardwood cuttings are taken during winter.

* excellent video found on Youtube

* Howard County, MD street tree planting

* photo taken on July 17 2011 in Columbia, MD

* photo taken on July 25 2013 in Columbia, MD

* photo taken on June 1 2014 @ Maryland Horticulturalist Club Tour, Ellicott City

* photos taken on Oct 23 2014 @ Washington, DC

* photos taken on Apr 13 2015 in Mt Airy, MD

* photo taken on July 25 2015 @ Niagara-on-the-Lake, Ontario

* photo taken on Dec 28 2015 in Columbia, MD

* photo taken on Mar 16 2015 in Columbia, MD

* photo taken on June 23 2016 in Columbia, MD

* photo taken on July 25 2016 in Columbia, MD

* photos taken on Apr 27 2017 in Columbia, MD

* photo taken on Nov 5 2017 in Columbia, MD

* photo taken during Feb 2019 in Columbia, MD

* photo taken on July 3 2020 in Columbia, MD

* london planetree in Indiana

* historic archive photo

foliage is anthracnose but not mildew resistant; it is otherwise the same as Platanus x acerifolia.

* photo taken on Nov 14 2016 in Howard Co., MD

Fast growing, reaching an average of 30 feet with a trunk diameter of 5 inches in 12 years and 72 x 40 x 1.7 feet in 20 years.
The distinctly 5 lobed foliage is deep green.
The fruit balls are produced in 2s or 3s.
Resistant to anthracnose and has good resistance to powdery mildew which is another common Sycamore problem.

Fast growing, dense and upright pyramidal in habit ( reaching only 45 feet in width at maturity ). The foliage is anthracnose and mildew resistant.

* exclamation london plane in Detroit, MI

* photo taken on June 7 2019 @ Univ. of Maryland, College Park

Fast growing, reaching up to 24 x 14 feet with a trunk diameter of 6 inches in 6 years and 50 feet in 25 years. The distinctly 5 lobed foliage is deep greem.
The fruit balls are produced singly or in 2s.
Resistant to anthracnose and has good resistance to powdery mildew which is another common Sycamore problem.

very tall and very fast growing. This tree is very strongly pyramidal. The handsome foliage is red-bronze at first turning to luxuriant mid-green. The foliage is very resistant to leaf diseases including anthracnose and mildew.

Leaves are purplish in summer turning purple-red in fall ( unusual for Sycamores )

'Old Bones'
pure white bark

upright to 100 feet in heightt with coarse bark and often slightly toothed 3 lobed leaves.

very narrow, very conical and very fast growing.

Light green leaves are very anthracnose & mildew resistant even in humid British Columbia.

Platanus cashmerana
Similar to P. orientalis, it is native to northern India. It is fast growing and disease resistant, making an excellent shade tree for climates with extreme summer heat such as Dallas, Texas.
Hardy zones 7 to 9, easy to grow from cuttings.

Platanus kerrii ( Kerrs Plane )
Native to southeast Asia; this is a tropical evrgreen Sycamore with leaves that are unlobed.
So far not known to be planted in North America though it should have potential in Florida.

Platanus mexicana ( Mexican Plane )
Native to northeast Mexico; this is a large deciduous ( evergreen in very mild climates ) tree to 100 feet however on ideal sites with extreme age it has potential of 135 feet tall; 100 feet wide with a trunk diameter up to 9 feet. The Mexican Plane is very fast growing.
The leaves are large and Maple like, 5 lobed and anthracnose resistant, up to 9 x 10 inches. They are silvery white below. The rough seedballs are up to 1.5 inches across.
The smooth bark is silvery-gray.
Hardy from zone 5 to 10 and very heat and alkaline soil tolerant. Move while very small as it resents transplanting.

* photos from unknown source on internet

Platanus occidentalis ( American Sycamore )
Native to eastern North America ( from eastern Nebraska to Iowa to southern Wisconsin to central Michigan to Goderich, Ontario to Toronto, Ontario to northern Vermont to central Maine; south to central Texas to far northern Florida...a separate population is also known from Wasaga Beach area of Ontario ); this is among the largest hardwood trees in North America and has a broad open crown made up of spreading branches. The American Sycamore is very fast growing and can reach over 100 feet in height with a trunk over 5 feet in diameter and often much larger. Some records: first year from seed - 20 inches; 30 feet in 5 years ( near Leamington, Ontario 1995 to 2000 ); 133 x 50 feet with trunk diameter of 1.5 feet in 20 years and the biggest canopy award goes to 200 feet tall with 105 foot width. The largest trunks ever recorded are 21 feet in width ( Gibson, Indiana - 1882 ) and another felled primeval hardwood forest giant that had a consistent diameter of 15 feet from 4 to 20 feet off the ground. Some massive relics remain including a 10 foot diameter tree on Corner Road in Mercersburg, PA. In the Windsor/Essex County, Ontario region; it was abundant in southern Essex County, the Lake Erie islands as well as the Ohio shore during the 1800s. Pure stands occurred in parts of the Canard River Valley during that time. Despite being well north of it's natural range, American Sycamores have reached up to 75 x 100 feet at Dominion Arboretum in Ottawa, Canada.
The foliage is 3 to 5 shallow lobed and Maple like in shape. They reach up to 12 x 12 inches ( though I measured individual leaves up to 24 inches long and wide on vigorous young in the Canard River Valley near Amherstburg, Ontario where some trees also had unusually pure white bark ).
The hanging rounded seed balls are usually single but sometimes occur in pairs.
The attractive flaking bark is smooth and pure white on the upper trunk and branches. The timber is valuable for both furniture and pulp.
Hardy zones 3 to 9 anywhere with between 30 and 80 inches of rain in a year ( unless irrigated ). It requires hot humid summers and does not thrive in most of western Europe where London Plane is planted instead. The American Sycamore are often prone to anthracnose during some years in late spring often rendering trees barren until leafing out again during early summer.

* photos taken in Laurel, MD on April 2002

* photos taken in Olney, MD on July 2005

* photo taken @ Montpelior Mansion in Laurel, MD on Oct 2002

* Taken in 2002 of Sycamore seedling planted 1996 on Cedar Island Drive, w of Leamington, ON

* photo taken on August 4 2010 @ Stratford, Ontario

* photos taken on April 14 2012 in Ellicott City, MD

* photo taken on Sep 3 2013 in Ellicott City, MD

* photos taken on Sep 5 2013 in Elkridge, MD

* photos taken on Sep 27 2013 in Laurel, MD

* photos taken on Oct 22 2013 in Towson, MD

* photo taken on Oct 31 2013 in Towson, MD

* photo taken on Aug 3 2014 @ National Zoo, DC

* photo taken on Oct 24 2014 in Columbia, MD

* photo taken on Apr 13 2015 in Howard Co., MD

* photos taken on Apr 21 2015 in Columbia, MD

* photos taken @ Middle Patuxent, Clarksville, MD on Apr 24 2015

* photo taken on Oct 23 2015 in Ellicott City, MD

* photo taken on Nov 4 2015 in Columbia, MD

* photos taken on Nov 28 2015 in Dauphin, PA

* photos taken on July 16 2016 in Bayfield, ON

* photos taken Aug 2016 @ Patuxent Research Refuge, Laurel, MD

* photos taken on Apr 14 2017 @ Patuxent Research Refuge, Laurel, MD

* photo taken on Jul 18 2017 @ Dominion Arboretum, Ottawa, ON

* photo taken on Aug 9 2020 in Columbia, MD

* photos taken on Oct 22 2020 in Columbia, MD

* historical archive photos

Platanus orientalis ( Oriental Plane )
Also called Oriental Sycamore. It is a massive, spreading, domed, deciduous tree native from southeastern Europe to Kashmir. Very fast growing; it can reach well over 100 feet in height. Some records are: fastest growth rate - trunk diameter increase of 0.8 inches; 3 years - 8 feet; 6 years - 15 x 12 feet; 12 years - 40 feet ( both the species and on a 'Digitata' growing in NC ); 20 years - 60 x 40 feet; 57 years - trunk diameter of 4 feet; 275 years - trunk diameter of 7 feet. The largest trees have reached 200 feet tall and 100 feet wide with trunks up to 15.5 feet in diameter. One ancient giant is rumored to have measured as much as 32 feet across, another is known to have survived 1214 years. The huge trunks on these trees are mottled brown, gray and greenish white.
The leaves, up to 12 x 12 inches in size, are palmately-lobed with 5 or 7 finely pointed lobes. They range from glossy bright to dark green. The leaves remain on the trees later in the fall than on other Platanus's.
The globe shape fruits occur in clusters from 2 to 6 and ripen to brown.
The Oriental Plane is often used as a street tree in the Southern Hemisphere in both Australia and Chile. Hardy from zone 5 to 9 depending on seed source some clones are only hardy north to zone 7 so selection of tree is very important. A clone from Hungary is not only completely anthracnose resistant but it is also hardy north to zone 5 and possibly 4 ( no damage recorded at -20 F ). Further testing should be done with the possible result of extending this drought tolerant trees range into parts of the Great Plains.
subsp. 'insularis' bright green leaves with toothed lobes. The fruits are hairy.

* photo of unknown source on internet

* historical archive photos

* excellent videos found on Youtube
link to excellent video found on Youtube

* excellent photo link found on internet

'Autumn Glory'
Superior to species with rich green foliage that turns intense orange to red during autumn.

Platanus racemosa ( California Plane )
A huge, long-lived, strong growing, broadly-columnar deciduous tree that is oftne dwarfted by drought in the wilds in its native range of central California to the Baja Peninsula. The California Plane can grow to 50 feet in 20 years and eventually exceed 100 feet. Some records include: 40 feet in 6 years and eventual sizes up to 200 feet tall; 160 feet wide with trunk diameters up to 12 feet! A trunk diameter of 16.6 feet has been recorded.
The thick leaves have 3 to 5 deep lobes; are dark green above and downy pale green below. They are around 10 inches long and wide though very rarely as much as 16 inches across.
The seeds are contained in bristly hanging brown balls that occur in clusters from 2 to 7.
Not as cold hardy as other Sycamores; this one is only hardy north to zone 6
however is more tolerant of hot windy or droughty sites than any other Sycamore.

* historical archive photos

* excellent video found on Youtube

'Augustine Henry'
Huge leaves to 16 x 14 inches! A large strong growing tree with a clear single upright trunk. Hardy north to zone 6

Leaves are more deeply cut and the bark is whiter than usual.
It also has superior mildew resistance.
Hardy north to zone 7.

Platanus wrightii ( Arizone Plane )
Another spectacular huge southwest native whose splendour in the wild is often stunted by the dry climate that it grows in. It is very similar to Platanus racemosa; forming a fast growing ( up to 5 feet per year ), broad-crowned tree, reaching up to 100 feet in height. This tree is probably capable with extreme age on ideal sites of 200 x 120 feet with a trunk diameter of 12 feet.
The leaves are large with 5 to 7 deep lobes and are white and hairy beneath. They reach up to 10 x 12 inches and unfortunately are prone to mildew. The leaves on the Arizona Plane typically hang down from the twigs. The foliage usually turns to yellow during autumn.
The clusters of greenish flowers are followed by densely packed smooth seed balls. The bark on the strong wooded trunks is white.
Hardy from zone 6 to 10 with unconfirmed reports of zone 3. This tree should be tested more outside its native range of Arizona, New Mexico and surrounding parts of Mexico.

* photos of unknown source on internet

* historic archive photo