{"id":3286,"date":"2021-08-19T00:13:34","date_gmt":"2021-08-19T07:13:34","guid":{"rendered":"https:\/\/depts.washington.edu\/hortlib\/pal\/pal-question-926\/"},"modified":"2024-04-11T11:01:13","modified_gmt":"2024-04-11T18:01:13","slug":"leaf-out-date-for-deciduous-trees","status":"publish","type":"pal","link":"https:\/\/depts.washington.edu\/hortlib\/pal\/leaf-out-date-for-deciduous-trees\/","title":{"rendered":"Leaf-out date for deciduous trees"},"content":{"rendered":"<p><strong>Can you direct me to a list of deciduous trees whose leaves generally emerge in early spring, or a list of trees ranked in order of their leaf emergence? I know this will vary from year to year and from individual tree to individual tree due to climate and genes, but if there is a list out there with a general sequenced time schedule, it would be a great tool for design.<\/strong><\/p>\n<p>&nbsp;<\/p>\n<p>An early American observer of the varying timing of leaf emergence was Henry David Thoreau, whose journals list leaf-out dates for the trees and shrubs he saw in Massachusetts in 1854. In fact, his data is now being used in <a href=\"http:\/\/www.nytimes.com\/2013\/04\/21\/books\/review\/a-man-for-all-seasons.html\">climate change research<\/a>. Though it&#8217;s a subject that hasn&#8217;t been much approached from a garden design standpoint, the increased interest in climate change means that more research on phenology and the leafing out sequence is becoming available. There are several articles by <a href=\"http:\/\/arnoldia.arboretum.harvard.edu\/pdf\/articles\/2007-65-2-climate-change-and-cherry-tree-blossom-festivals-in-japan.pdf\">Richard Primack<\/a> in the Arnold Arboretum newsletter, <a href=\"http:\/\/arnoldia.arboretum.harvard.edu\/pdf\/articles\/2003-62-3-the-special-role-of-historical-plant-records-in-monitoring-the-impact-of-climate-change.pdf\"><em>Arnoldia<\/em><\/a>. <a href=\"https:\/\/www.bu.edu\/biology\/people\/profiles\/richard-b-primack\/\">Primack<\/a> (of Boston University) is a specialist in this topic. Primack and Caroline Polgar co-authored <a href=\"http:\/\/arnoldia.arboretum.harvard.edu\/pdf\/articles\/2011-68-4-leaf-out-dates-highlight-a-changing-climate.pdf\">&#8220;Leaf-out phenology of temperate woody plants: from trees to ecosystems&#8221;<\/a> (<em>Arnoldia<\/em>, Volume 68, Issue 4,2011) which states that &#8220;maples (<em>Acer<\/em> spp.), birches, alders (<em>Alnus<\/em> spp.), and poplars&#8221; tend to leaf out earlier, while &#8220;oaks, ashes (<em>Fraxinus<\/em> spp.), and hickories (<em>Carya<\/em> spp.)&#8221; are among the later-leafing trees.<\/p>\n<p>The article <a href=\"https:\/\/www.jstor.org\/stable\/2461303?seq=1#page_scan_tab_contents\">&#8220;Why Do Temperate Deciduous Trees Leaf Out at Different Times? Adaptation and Ecology of Forest Communities,&#8221;<\/a> (<em>The American Naturalist<\/em> December 1984, Martin J. Lechowicz) has a chart (p. 825) showing the tree species the author studied leafing out in this order:<\/p>\n<p>&nbsp;<\/p>\n<ul>\n<li><em>Acer rubrum<\/em><\/li>\n<li><em>Populus tremuloides<\/em><\/li>\n<li><em>Betula papyrifera<\/em><\/li>\n<li><em>Sorbus americana<\/em><\/li>\n<li><em>Acer saccharinum<\/em><\/li>\n<li><em>Betula alleghaniensis<\/em><\/li>\n<li><em>Ulmus americana<\/em><\/li>\n<li><em>Tilia americana<\/em><\/li>\n<li><em>Quercus macrocarpa<\/em><\/li>\n<li><em>Fraxinus pennsylvanica<\/em><\/li>\n<li><em>Populus grandidentata<\/em><\/li>\n<li><em>Fraxinus nigra<\/em><\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>Another chart on the same page compares 1980 and 1981 leafout dates, with Populus tremuloides and <em>P. balsamifera<\/em> and <em>Betula<\/em> species consistently leafing early, followed by <em>Acer<\/em> and <em>Prunus<\/em>, then <em>Fagus<\/em> and <em>Populus grandidentata<\/em>, then <em>Fraxinus<\/em> and <em>Tilia<\/em>, and finally <em>Carya<\/em> and <em>Juglans<\/em>.<\/p>\n<p>You may want to read a short article in the March 11, 2015 online version of <a href=\"http:\/\/conservationmagazine.org\/2015\/03\/200-years-of-citizen-science-predict-the-future-of-forests\/\">Conservation Magazine<\/a> on predicting the future of forests, based on two centuries of data from citizen scientists in England. Here is an excerpt:<br \/>\n&#8220;It is likely that the variation in each species&#8217; sensitivities to both spring forcing and winter chilling will mean that forests will look quite different in the future. Those species for whom spring forcing is most important will grow leaves earlier in the year; those for whom the autumn and winter chill is more critical could leaf later in the year. Eventually, a late-leafing species like oak might wind up growing its leaves earlier than an early-leafing species like birch.&#8221;<\/p>\n<p>Another resource that may help you determine the leaf-out date of specific trees is <em>The Botanical Garden: volume 1: Trees &amp; Shrubs<\/em> by Roger Phillips and Martyn Rix (Firefly, 2002). The book presents photos of branch samples from many tree species, often showing the young leaves associated with a date (though not with the geographical location; bear in mind that the authors reside in England). While it doesn&#8217;t have such a photo for every tree, it might have enough trees for you to get useful data.<\/p>\n<div class=\"taxonomy-keyword has-text-align-right wp-block-post-terms\"><a href=\"https:\/\/depts.washington.edu\/hortlib\/keyword\/leaves\/\" rel=\"tag\">Leaves<\/a><span class=\"wp-block-post-terms__separator\">, <\/span><a href=\"https:\/\/depts.washington.edu\/hortlib\/keyword\/plant-phenology\/\" rel=\"tag\">Plant phenology<\/a><span class=\"wp-block-post-terms__separator\">, <\/span><a href=\"https:\/\/depts.washington.edu\/hortlib\/keyword\/trees\/\" rel=\"tag\">Trees<\/a><\/div>\n","protected":false},"excerpt":{"rendered":"<p>Can you direct me to a list of deciduous trees whose leaves generally emerge in early spring, or a list of trees ranked in order of their leaf emergence? I know this will vary from year to year and from individual tree to individual tree due to climate and genes, but if there is a list out there with a general sequenced time schedule, it would be a great tool for design. &nbsp; An early American observer of the varying&#8230;<\/p>\n<div><a class=\"more-link\" href=\"https:\/\/depts.washington.edu\/hortlib\/pal\/leaf-out-date-for-deciduous-trees\/\">Continue reading <span class=\"screen-reader-text\">Leaf-out date for deciduous trees<\/span><\/a><\/div>\n","protected":false},"author":6,"featured_media":0,"menu_order":0,"template":"","keyword":[193,929,287],"class_list":["post-3286","pal","type-pal","status-publish","hentry","keyword-leaves","keyword-plant-phenology","keyword-trees"],"acf":[],"_links":{"self":[{"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/pal\/3286"}],"collection":[{"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/pal"}],"about":[{"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/types\/pal"}],"author":[{"embeddable":true,"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/users\/6"}],"wp:attachment":[{"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/media?parent=3286"}],"wp:term":[{"taxonomy":"keyword","embeddable":true,"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/keyword?post=3286"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}