Antagonistic effects of growing season and autumn temperatures on the timing of leaf coloration in winter deciduous trees

The Old World terrestrial orchid genus Nervilia Commerson ex Gaudichaud-Beaupré in Freycinet (1829: 421, t. 35) remains poorly known, especially in Asia. It is diagnosed by its hysteranthous habit, in which a single, terminal, one–several-flowered inflorescence and a single ovate to cordate leaf emerge in succession from a single globose tuber. This temporal separation of flowers and leaves makes complete herbarium collections rare. Some species have been described only from flowers, others have been recorded only from leaves, and occasionally the two are mismatched on the same herbarium sheet. The situation is compounded by the ephemeral nature of the plants; the flowering phase is brief, fructification is rapid with fruit set usually occurring prior to leaf flush, and all above-ground parts die back at the end of the growing season, making plants difficult to locate in the field and under-represented in herbaria. Accordingly, species circumscriptions are often inadequate, vague and sometimes overlapping, and the loss or concealment of potentially useful characters (e.g. leaf coloration, lip indumentum) in dried herbarium (especially type) material challenges their critical re-evaluation.

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Strong non‐growing season N uptake by deciduous trees in a temperate forest: A 15 N isotopic experiment

Journal of Ecology ◽

10.1111/1365-2745.13754 ◽

2021 ◽

Author(s):

Linna Ma ◽

Xiaofeng Xu ◽

Chaoxue Zhang ◽

Yixia Lv ◽

Guofang Liu ◽

...

Keyword(s):

Temperate Forest ◽

N Uptake ◽

Growing Season ◽

Deciduous Trees

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Chemical characteristics of the foliage of some deciduous trees in southeastern Ontario

Canadian Journal of Botany ◽

10.1139/b82-251 ◽

1982 ◽

Vol 60 (10) ◽

pp. 2037-2045 ◽

Cited By ~ 42

Author(s):

Robert E. Ricklefs ◽

Kathryn K. Matthew

Keyword(s):

Unit Area ◽

Dry Weight ◽

Growing Season ◽

Chemical Characteristics ◽

Deciduous Trees ◽

Crude Fibre ◽

Leaf Toughness ◽

Southern Ontario ◽

Calcium And Magnesium ◽

Nitrogen Phosphorus

We collected foliage from 34 species of broad-leaved, deciduous trees in southern Ontario and determined an index of leaf toughness, weight per unit area, percent water, and percent of dry weight as available carbohydrate, crude fibre, hemicellulose, holocellulose, lignin, polyphenols, nitrogen, phosphorus, ash, potassium, calcium, and magnesium. We analyzed variation in these constituents within samples, among three sampling periods during one growing season, and among species.

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No risk - no fun: The tradeoff between avoiding frost and maximizing growth

10.5194/egusphere-egu2020-21586 ◽

2020 ◽

Author(s):

Frederik Baumgarten ◽

Yann Vitasse ◽

Arthur Gessler

Keyword(s):

Prunus Avium ◽

Light Transmission ◽

Growth Parameters ◽

Growing Season ◽

Deciduous Trees ◽

Season Length ◽

Freezing Resistance ◽

Spring Frost ◽

Growing Season Length ◽

Temperature Thresholds

AbstractLeaf-out timing is crucial for the fitness of deciduous trees inhabiting temperate and higher latitudes. Optimal leaf-out allows minimizing freezing damages and herbivory pressure while maximizing growing season length and resource uptake in order to increase their competitiveness. However only a few attempts have been made to classify species according to their strategy along this trade-off.Using climate chambers, we artificially provoked 5 different flushing dates that span the maximum possible range of natural occurring flushing dates of 4 tree species (Prunus avium, Carpinus betulus, Fagus sylvatica and Quercus robur). Shortly after each of the five leaf-out timings, 12 saplings per species were exposed to a frost treatment that is expected to either kill all leaves (LT100, i.e. lethal temperature killing 100% of the leaves) or to partially damage them. These temperature thresholds have been adapted to each species according to their freezing resistance found in the literature. A subset of 12 indviduals per species served as a control and were not subjected to a frost treatment. Shortly after the frost treatment, all saplings were planted outside in the ground under a shading net (~-60% of light transmission) simulating below canopy conditions at the WSL research facility near Z&#252;rich.Growth parameters (diameter, height) and recovery state (percentage of greenness compared to the control) were regularly measured during the consecutive growing season as well as the leaf coloring in autumn 2019. Preliminary results suggest that cherry and oak have recovered more than 80% by the end of the growing season, whereas beech and hornbeam only recovered about 50%. Oak was the fastest species to recover, already reaching 80% three weeks after the frost treatment. Our results allow to better quantify to what extend damaging spring frost reduces competitiveness for resources (light, nutrients) among species.

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SUNBATHED ASPEN GROW TO SHOW HOW SUNLIGHT INFLUENCES ASPEN LEAF CHANGES IN THE AUTUMN SEASON

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xliv-m-2-2020-105-2020 ◽

2020 ◽

Vol XLIV-M-2-2020 ◽

pp. 105-110

Author(s):

S. K. Weidler ◽

R. Sivanpillai

Keyword(s):

Populus Tremuloides ◽

Color Change ◽

Growing Season ◽

Environmental Modeling ◽

University Of Wyoming ◽

Learning Activity ◽

Deciduous Trees ◽

Leaf Color ◽

Inquiry Based Learning ◽

Observation Network

Abstract. Every autumn, leaves of deciduous trees change from green to other colors and eventually drop to the ground. The rate of color change is influenced by a several factors including the amount of sunlight and temperature. As part of an inquiry-based learning activity, University of Wyoming students have been recording leaf color change (% change) and its drop date (%) in Aspen trees (Populus tremuloides) growing in Laramie (WY) using NEON’s (National Ecology Observation Network) Phenology data form. In this study, the data recorded from 2015 through 2018 were analyzed to identify trends in the rate of color change in dry and normal years. Trees that were in an area with a high amount of shade were observed to change leaf color and drop their leaves faster than those in areas that received more sun. This pattern was consistent even in years that experienced winter-like conditions in September. Findings from this multi-year study indicate that future environmental modeling projects must factor in the amount of sunlight received by aspen trees in the growing season into account.

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Predicting leaf traits of temperate broadleaf deciduous trees from hyperspectral reflectance: can a general model be applied across a growing season?

Remote Sensing of Environment ◽

10.1016/j.rse.2021.112767 ◽

2021 ◽

pp. 112767

Author(s):

Litong Chen ◽

Yi Zhang ◽

Matheus Henrique Nunes ◽

Jaz Stoddart ◽

Sacha Khoury ◽

...

Keyword(s):

General Model ◽

Leaf Traits ◽

Growing Season ◽

Deciduous Trees ◽

Hyperspectral Reflectance

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Motor–manual, mechanical, and herbicide release affect early successional vegetation in northwestern Ontario

The Forestry Chronicle ◽

10.5558/tfc73061-1 ◽

1997 ◽

Vol 73 (1) ◽

pp. 61-68 ◽

Cited By ~ 31

Author(s):

F. Wayne Bell ◽

R. A. Lautenschlager ◽

Robert G. Wagner ◽

Doug G. Pitt ◽

John W. Hawkins ◽

...

Keyword(s):

Univariate Analysis ◽

Growing Season ◽

Deciduous Tree ◽

Deciduous Trees ◽

Percent Cover ◽

Aerial Application ◽

Northwestern Ontario ◽

Pre Treatment ◽

The Individual ◽

Successional Vegetation

Cover and height of vegetation before and one growing season after: 1) motor-manual cutting, 2) mechanical brush cutting (Silvana Selective/Ford Versatile), 3) aerial application of Release® (a.i. triclopyr) herbicide, 4) aerial application of Vision® (a.i. glyphosate) herbicide, and 5) control (no treatment) were quantified. Multivariate analysis permitted the study of vegetation response as a whole, while accounting for correlations that exist among the individual vegetation groups. Univariate analysis were used to study the responses of individual vegetation groups. Although no pre-treatment differences in percent cover were observed (P = 0.128), deciduous tree, shrub, forb, grass, and sedge groups responded differently to the treatments after one growing season (P < 0.018). Post-treatment cover of deciduous tree and shrub groups was lower in herbicide treated plots than in cut plots. Forb, grass and sedge covers varied greatly among treatments. Brush saw and Silvana Selective treatments decreased cover of deciduous trees. Release® decreased cover of deciduous trees and shrubs. Vision® decreased cover of deciduous trees, shrubs and ferns. Cover of all vegetation groups increased on the untreated control. Among the conifer release treatments examined, Vision® reduced woody and herbaceous vegetation most. Key words: clearing saw, conifer release, Falingsnow Ecosystem Project, glyphosate, herbicides, Release®, Silvana Selective, spruce, triclopyr, vegetation management, Vision®.

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