24
votes
Accepted
What is Growing on These Tree Leaves? (Image)
This is actually not a gall as other answers have suggested.
This is likely a fungus called Cedar-apple rust (Gymnosporangium juniperi-virginianae).
The fungus only thrives in the presence of both ...
14
votes
Are these birch or aspen trees?
Turns out this is harder than it seems from just the picture...
The three candidates I think one could most argue for are:
Quaking Aspen (Populus tremuloides)
Paper Birch (Betula papyrifera)
Grey ...
14
votes
Accepted
Why do birches have a white bark?
It is protection against rapid warming of the cambium layer. A lot of far northern timber has light colored bark which reflects sunlight. The rapid heating from very cold after sunrise can actually ...
14
votes
Accepted
Help ID this South Indian fruit-bearing tree
This looks like Muntingia calabura, the Jamaica Cherry.
pic source
pic source
It is indigenous to tropical America and often planted in Asia.
It is edible and used in jam, cake and fruit drinks. The ...
13
votes
How long does DNA last in wood?
DNA can remain intact in wood, enough to perform useful identification, for centuries (this study had success with wood from ~1300 AD). However, successfully extracting DNA from the wood may be ...
11
votes
Accepted
Identify this tree?
Based on the distinctive leaf shape and placement of the fruit along the stem that appears to be a papaya.
If so then the plant should "bleed" latex (a milky white fluid) when damaged. You can test ...
10
votes
Accepted
What is this small tree?
This is very likely some species of Viburnum.
Viburnum is a genus of about 150–175 species of shrubs in the Adoxaceae family that are primarilly native throughout the temperate Northern Hemisphere.
...
10
votes
Accepted
Is it true to say that the genome of trees includes or at least "encapsulates" the genome of mushrooms?
No.
Evidence: If you go to the TreeGenes site and examine those tree genomes that have been sequenced you won’t find any fungal chromosome sequences. (And vice versa.)
Reason: Although trees and ...
9
votes
Accepted
What is the name of this tree with compound leaves?
It is Cussonia spicata, It is one of the favorite foods of wild elephants.
The attractive leafs grow from the end of thick branches to form rounded heads.
Source
Wikipedia
9
votes
Can someone help me to identify what kind of pear is this?
Plu Code 4413 is a bosc pear (a cultivar of Pyrus communis).
From the PLU search tool available via the International Federation for Produce Standards
FYI: take a close look at the pear you're ...
8
votes
Accepted
Australian Tree Identification - maybe pine?
Native cherry, Cherry ballart or Cypress cherryn belongs to the sandalwood family of plants.
http://en.wikipedia.org/wiki/Exocarpos_cupressiformis
8
votes
Accepted
At what temporal scales do forest structures change?
This question is too broad. What type of temperate forest?
The European Environment Agency recognized dozens of temperate forest types:
...
8
votes
Accepted
Identifying a shrub with unusual "many shoots" growth behavior
Possibly an example of a "Witch's Broom."
Witch's Broom is a deformity in plants (typically woody species) which typically causes dense patches of stems/shoots to grow from a single point on the ...
8
votes
Accepted
Less oxygen in winter?
Pretty interesting question: The short answer to it is: Yes, the seasonal O2 levels vary with the season and this can be measured.
The paper in reference 1 says that this is connected to two phenomena:...
8
votes
Accepted
What is the fate of the typical tree?
This is a great question.
Without going into too much detail, there is a series of studies done in northeastern US temperate forests (specifically at Great Mountain Forest in Connecticut, USA) on the ...
7
votes
What tree is this?
It looks like a Purging Buckthorn (Rhamnus cathartica) - Native to Europe and North Asia. It is the food-plant of the Brimstone butterfly.
See Woodland Trust
If it is isolated from others perhaps it ...
7
votes
Why does this plum/apricot hybrid look like brains?
It is difficult to say, but it is likely due to disease. Many plant diseases have the effect of convincing plant tissues that they are some other organ than what they actually are, which leads to ...
7
votes
Accepted
Leaf formation on unknown tree: cocoon or something else?
Based on the location and assuming this isn't a domesticated hazelnut there are two likely hazelnut species. The lack of the distinctive "beak" seen on the Beaked hazelnut means this is most likely ...
7
votes
Accepted
How related are trees?
The word "tree" is a not a taxonomic classification, but a human perceptual clustering based on form and size. The word "fish" has a similar problem, covering a vast collection of ...
6
votes
What kind of tree is this?
This is a Birch tree, Betula sp., probably B. pendula, a common species in Denmark that also has hanging branches. It can be identified by the white bark and the leaves, that are not as long as a ...
6
votes
Accepted
What plant/tree is this?
Your pictures are a bit vague, but I think recognize Euonymus europeus, the spindle tree. So I assume the picture comes from Europe? The fruits are encapsulated in pink capsule, the fruit itself is ...
6
votes
Accepted
Identify this indoor plant with strange stem-like leaves
Looks like a Pencil Tree (Euphorbia tirucalli), sometimes called "pencil plant", "pencil cactus" or "milkbush." This "leafless-looking" plant is not actually a ...
6
votes
Are there any trees that prefer to grow on the floor of water bodies but protrude to the air?
Mangrove swamp trees and shrubs immediately spring to mind. There are many species that fall into this category of trees that grow in intertidal and costal locations. They prefer locations where salt ...
6
votes
Accepted
Do trees in a forest generally grow in a lattice formation?
For most trees and plants, distribution is spatially highly variable. Thinking about the lifecycle of plants—their seeds are non-randomly dispersed, the seedlings and saplings grow in different biotic ...
6
votes
Why does this plum/apricot hybrid look like brains?
This is a guess, but perhaps the result of an infection by a fungal plant pathogen related to Taphrina deformans. T deformans infects species of the genus Prunus (i.e. the genus of prunes and apricots)...
6
votes
Is it true to say that the genome of trees includes or at least "encapsulates" the genome of mushrooms?
A symbiotic relationship is entirely unrelated to the genetic origins of the participating organisms. Symbiosis only requires that the organisms interact in a manner that benefits both parties. There ...
6
votes
Accepted
What's the name of this green fruit with little pikes fallen from a city tree on the pavement?
It is horse chestnut it is very common to plant chestnut trees in public parks and a lot of people do have them around their property and by the side of many roads.
What you have in your picture is ...
6
votes
Accepted
Coniferous tree with alternating bunches of short needles (Toronto area)
Short Answer
Larix laricina, commonly called Tamarack or American Larch is a deciduous conifer with short-needle-like leaves arranged in bunched fascicles in a alternating (sometimes whorled) ...
6
votes
Accepted
Growing peaches from (supermarket) bought seeds
I'll admit I'm not super familiar with peaches specifically, but many agricultural strains are carefully selected hybrids of true-breeding plants.
That means that you take two breeding stocks that are ...
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