a b "Diversity and evolution of monocots" (PDF). University of Wisconsin. Archived (PDF) from the original on 22 October 2016 . Retrieved 22 September 2014. Street trees". Greenspace initiative. Forestry Commission. Archived from the original on 4 March 2016 . Retrieved 20 September 2014. Sneader, W. (2000). "The discovery of aspirin: A reappraisal". BMJ (Clinical Research Ed.). 321 (7276): 1591–1594. doi: 10.1136/bmj.321.7276.1591. PMC 1119266. PMID 11124191. Tea cultivation and practices". Upasi Tea Research Foundation. Archived from the original on 17 October 2012 . Retrieved 13 September 2012.

English oak". Old Knobbley. 2007. Archived from the original on 8 September 2012 . Retrieved 25 July 2012. Cellania, Miss (28 February 2012). "10 Artists Who Work in Trees". Mental Floss. Archived from the original on 3 August 2014 . Retrieved 20 September 2014. In temperate climates there is a sudden movement of sap at the end of the winter as trees prepare to burst into growth. In North America, the sap of the sugar maple ( Acer saccharum) is most often used in the production of a sweet liquid, maple syrup. About 90% of the sap is water, the remaining 10% being a mixture of various sugars and certain minerals. The sap is harvested by drilling holes in the trunks of the trees and collecting the liquid that flows out of the inserted spigots. It is piped to a sugarhouse where it is heated to concentrate it and improve its flavour. Similarly in northern Europe the spring rise in the sap of the silver birch ( Betula pendula) is tapped and collected, either to be drunk fresh or fermented into an alcoholic drink. In Alaska, the sap of the sweet birch ( Betula lenta) is made into a syrup with a sugar content of 67%. Sweet birch sap is more dilute than maple sap; a hundred litres are required to make one litre of birch syrup. [115]

Transport in plants". BioTech. Cronodon Museum. 28 January 2007. Archived from the original on 14 October 2012 . Retrieved 21 July 2012. a b c Gschwantner, Thomas; etal. (2009). "Common tree definitions for national forest inventories in Europe". Silva Fennica. 43 (2): 303–321. doi: 10.14214/sf.463. Trees are either evergreen, having foliage that persists and remains green throughout the year, [27] or deciduous, shedding their leaves at the end of the growing season and then having a dormant period without foliage. [28] Most conifers are evergreens, but larches ( Larix and Pseudolarix) are deciduous, dropping their needles each autumn, and some species of cypress ( Glyptostrobus, Metasequoia and Taxodium) shed small leafy shoots annually in a process known as cladoptosis. [5] The crown is the spreading top of a tree including the branches and leaves, [29] while the uppermost layer in a forest, formed by the crowns of the trees, is known as the canopy. [30] A sapling is a young tree. [31]

Zotz, Gerhard (2016). Plants on Plants – The Biology of Vascular Epiphytes. Springer. ISBN 978-3-319-39237-0. Archived from the original on 19 August 2020 . Retrieved 14 November 2017. Cork Flooring is Environmentally Sustainable". AZoM.com. 27 February 2006. Archived from the original on 7 November 2012 . Retrieved 26 July 2012. Sager, Kim. "Whitebark Pine Seeds, Red Squirrels, and Grizzly Bears: An Interconnected Relationship". BEHAVE: Behavioral Education for Human, Animal, Vegetation and Ecosystem Management. Archived from the original on 9 December 2013 . Retrieved 23 July 2012.Ruxton, Graeme D.; Schaefer, H. Martin (2012). "The conservation physiology of seed dispersal". Philosophical Transactions of the Royal Society. 367 (1596): 1708–1718. doi: 10.1098/rstb.2012.0001. PMC 3350653. PMID 22566677. Tanneries, Description of the Tanning Process". Food and Agriculture Organization of the United Nations. Archived from the original on 22 August 2011 . Retrieved 26 July 2012.