Juglans regia

Juglans regia L., Sp. Pl. 997 1753. (Syn: Juglans duclouxiana Dode; Juglans fallax Dode; Juglans kamaonia (C. DC.) Dode; Juglans orientis Dode; Juglans regia subsp. fallax Popov; Juglans regia var. kamaonia C. DC.; Juglans regia var. sinensis C. DC.; Juglans sinensis (C. DC.) Dode; Regia maxima Loudon ex C.DC. (Unresolved));

Common walnut, Persian walnut or English walnut;

/wp-content/uploads/2020/10/IMGA0257.jpg

VoF Week: ID the Tree please.:
The tree was photographed near Govindghat on 16.08.2012. Kindly id the same.

this is the very famous and well known dry fruit… Walnut.. Juglans regia.. Akhrot.

Juglans regia ATJUNE2016/11 : 3 posts by 2 authors. Attachments (5)

Juglans regia
Persian walnut, English walnut, Akhrot
Nearby Shimla
2012-2016

Attachments (1)

Thanks, …, for the detailed photographs.

Juglans regia : 2 posts by 2 authors. Attachments (3)
Sharing some pictures of Juglan regia shot at Kathmandu on 2 June 2016 at 4500 ft

/wp-content/uploads/2020/10/walnut-crop.jpg

Walnut tree, fruit : 21 posts by 12 authors. Attachments (4)
These images have been taken by my brother, …, who is based in Srinagar.

English Walnut Juglans regia

…, nice photos. Last year during our visit to Kashmir we go to see lots of Walnut trees with immature fruits. The tree is very beautiful and is allelopathic – meaning it does not allow any other plants to grow under or near it.

Thank you, … I did not know that walnut is an allelopathic tree. What are the other common trees that are allelopathic? Are neem and banyan?

Yes walnut is the commonest example of allelopathy I would tell my students. Hardly any plant grows beneath it.

Here are the photographs of Black walnut, Juglans nigra from California in USA. Attachments (2)

Thank you for sharing, … The leaves look so different!

Tamarind also exhibits allelopathic effect.

I suppose some conifers like pinus roxburghii also have this property.
Due to the acidic nature of dried leaves which fall on the ground no other vegetation can grow. Am I right?

Good to see Walnut tees from India and California!

I do not know about walnut tree and allelopathy. I have seen that nothing grows under a tree where the shade is so thick that no sunlight penetrates. I have seen someone claim that tamarind tree has also the allelopathy effect. I can not agree to that as I have a couple of them and we have coffee growing very well underneath it. I had a very healthy pepper vine on them and also thick growth of weeds growing under its shade.
It is worth observing the rainfall in the area where such observations are made. Another point to be observed is are the walnut trees so close to each other that no sunlight penetrates under the thick canopy.
We have a few jack fruit trees so close to each other and no weeds would grow underneath it in spite of very nice mulch and nice loamy soil. Once we regulated the shade, we found lush growth underneath it.
This though is the observation of a lay person.

Tamrind root exudates have allelopathic competence and are evaluated for sustainable weed management programs.
The bark and the seeds have differential (inhibitory and excitatory) allelopathic effects. They have some growth regulators which additively or synergestically involve in plant specific expression.

nice info about the allelopathic effects of tamarind exudates.

Thank you for the enlightenment. You will observe that I have
mentioned that these are the observation of a lay person. For your reference, I will send you the picture of the growth under my tamarind tree a few hours later. Thank you once again. I would love to receive the study that has been conducted on the subject.

I don’t know much about Tamarindus but Juglans allelopathic effects I know even before I was a student of botany. Hardly any plant grows beneath or in the vicinity of Walnut tree. Juglans (both species J. nigra the black walnut of America and J. regia, the English walnut) leaves, bark, stem, fruit pericarp and roots contain a colourless non-toxic chemical hydrojuglone. When exposed to air or soil chemicals it is oxidized into highly toxic allelochemic compound juglone. Rain washes juglone from leaves and other parts and carries it into soil. It is toxic to both herbaceous and woody species.

Just for additional information, bark of Juglans fresh or dried is used for cleaning teeth in the same way as Acacia twigs in many parts of North India (Datun). On exposure to air and convertion to juglone the gums get orange-red colour, and is especially used by ladies to both clean teeth and colour gums.

But then there are always plants which are resistant to juglone, and these can grow/can be planted adjacent to Juglans trees. Among trees the resistant species are various species of maple, Ailanthus glandulosa, Quince, Red cedar, Sweetgum, pine, oak and Black locust (we often find this Robinia pseudoacacia growing alongside Juglans in Kashmir). Among shrubs and climbers Roses, Grape vine, Hazelnut and Thuja are resistant. Several herbaceous plants like species of Brassica, Cichorium, Convolvulus, etc. also manage to grow.
Not having first hand information but the plants growing or grown under Tamarind may similarly be resistant to Tamarind allelopathy.

Am attaching pictures of a tamarind tree with the luxurious growth of
other plants beneath its shade. I would appreciate if any more light
is thrown on the subject. It would be very useful for a farmer.

Please find the study in the links given below. Hope its useful to
you.
http://www.springerlink.com/content/xx2j657m24twu832/
http://www.springerlink.com/content/p21qhl0431018786/

Allelopathic effects may differ according to the climatic conditions of the area.

Agreed with … And Allelopathy never means only suppression. Both inhibitory as well as stimulatory Allelopathic interactions exist in Nature.

Thank You …
Thanks to you , I have learn t something today.

What allelopathic effects does Grevillea robusta have?

/wp-content/uploads/2020/10/Hazelnut-tree-0.jpg

/wp-content/uploads/2020/10/DSCN0898walnut2.jpg

/wp-content/uploads/2020/10/Hazelnut-raw-5.jpg

/wp-content/uploads/2020/10/Hazelnut-fruit2-9.jpg

/wp-content/uploads/2020/10/Hazelnut-fruit-2.jpg

Srinagar;

PLANT 75SMP JUN 09 Manali – indiantreepix | Google Groups

Images of two nut trees, fruit – efloraofindia | Google Groups

Juglans regia L.: 3 very high res. images.

Location: Juphal, Dolpa, Nepal

Altitude: 2400m.

Date: 22 June 1022
Habit : Wild

Juglans regia L.: 4 high res. images.

Location: Gakar Khola, Lukum, Rukum West, Nepal

Date: 31 May 2023

Elevation: 2500 m.
Habit : Wild

On the walnut tree in my garden walnuts are borne in pairs. It was interesting to find that on this tree they are borne as triplets.

Is this the species from which we get walnuts sold in the market ?

The tree in my garden is of the so called “Kaghzi” variety which is so named because the shell is so thin that it can be broken by a sharp blow . “Kaghazi” means paper thin. This is a rather uncommon variety. As … has suggested this could be the reason for fruits being borne in pairs instead of triplets.

Actually, there may be some misunderstanding of this sp. This one is found in the wild and the nut wall is very very hard to break and the nut contents are also very less in amount and difficult to retrieve from the nut wall compared to commercially grown walnuts. Normally, we use a safety pin or any pointed object to retrieve the nuts. For your information, this is a very essential dry fruit (a must) necessary during Bhai Tika (Bhai Duj) in Nepali Hindu culture. Its nut bark is also very tometose compared to the commercial variety. I think someone should study this sp. and find out the differences. I shall post you the images of ready nuts if I can find them in the market !

Forests of wild variety are also found in Kashmir. Its local name is “Hant”. It is prized not for its fruit but for its wood which is fine grained and takes a high polish. It is used for making fine furniture and for woodcarving. A woodcarver once told me that fine carving is only possible on walnut wood. In olden days it was much sought after by British officers for making rifle butts.

Juglans regia cultivar from Srinagar: 9 images.
Am posting photos of a walnut cultivar from Srinagar. This is so called “Kaghzi ” variety which has a very thin shell. Male (Staminate) flowers are borne in catkins and Female(Pistillate) flowers occur as pairs. Staminate flowers have about a dozen stamens. The pollen grains have a peculiar attractive shape when seen under a microscope. Both staminate and pistillate are borne on the same plant. Hill people eat the stalks of the catkins of all varieties which are said to taste like spinach.