Juniper

Junipers are special trees and shrubs that belong to the genus Juniperus. They are part of the cypress family and grow all around the Northern Hemisphere. You can find them in Africa, the Arctic, Asia, and Central America.

Depending on how scientists group them, there are between 50 and 67 different kinds of junipers. One amazing place to see junipers is in southeastern Tibet and the northern Himalayas, where they grow very high—up to 4,900 metres (16,100 feet) above sea level. This shows how strong and adaptable these plants can be.

Description

Junipers come in many sizes and shapes, from tall trees to low shrubs. They keep their leaves all year and have either needle-like or scale-like leaves. Their seed cones look like small, berry-like fruits and can be blue, red-brown, or orange. These berries are often used as a spice.

Junipers can bloom and release pollen many times a year in warmer areas. Some junipers have two kinds of leaves: needle-like on young plants and scale-like on older ones. Their leaves can be sharp and prickly, which helps tell them apart from similar plants. Junipers do not have flowers but produce seeds that can wait a long time until they grow.

Classification

Junipers are trees and shrubs in a group called Juniperus. They grow all over the Northern Hemisphere, from tropical Africa to the Arctic, and in parts of Asia and Central America. Some very tall juniper forests grow in southeastern Tibet and the northern Himalayas, reaching up to 4,900 metres (16,100 ft) above sea level.

Junipers are divided into three main groups based on science. One group has one kind with large, blue cones. Another group has 14 kinds with blue or red cones, mostly found in the Eastern Hemisphere, one in North America, and one that grows everywhere north. The third group has about 60 kinds with cones of different colors, split between the eastern and western hemispheres. Scientists now think these three groups should be separate.

Sections

The juniper group has been divided in different ways. A system from 2013 used three sections based on molecular phylogenetic data:

• Section Caryocedrus – 1 kind with large, blue, woody cones with three seeds; from the Mediterranean
• Section Juniperus – 14 kinds with blue or red seed cones, often with three seeds; 12 kinds from the Eastern Hemisphere, one only in North America, and one kind, J. communis, found everywhere north
• Section Sabina – about 60 kinds with seed cones of different colors and one to 13 seeds; about half from each hemisphere Juniperus sect. Sabina was divided further.

A new way to group plants from 2022 recognized these sections as three separate groups: Arceuthos for section Caryocedrus, Sabina for section Sabina, and Juniperus sensu stricto for section Juniperus.

Species

Juniperus sect. Caryocedrus

Cones have three seeds stuck together; needles have two rows of small holes. One kind:

• Juniperus drupacea – Syrian juniper

Juniperus sect. Juniperus

These junipers have needle-like leaves, growing in groups of three and joined at the base. Kinds include:^{[citation needed]}

• Juniperus sect. Juniperus subsect. Juniperus – cones with three separate seeds; needles with one row of small holes
  • Juniperus communis – common juniper
    • Juniperus communis subsp. alpina – alpine juniper
  • Juniperus conferta, syn. Juniperus rigida var. conferta (Parl.) Patschke – shore juniper
  • Juniperus rigida – Temple juniper or needle juniper
• Juniperus sect. Juniperus subsect. Oxycedrus – cones with three separate seeds; needles with two rows of small holes
  • Juniperus brevifolia – Azores juniper
  • Juniperus cedrus – Canary Islands juniper
  • Juniperus formosana – Chinese prickly juniper
  • Juniperus lutchuensis, syn. Juniperus taxifolia var. lutchuensis (Koidz.) Satake – Ryukyu juniper
  • Juniperus oxycedrus – Western prickly juniper, cade juniper
  • Juniperus macrocarpa – large-berry juniper

Juniperus sect. Sabina

These junipers have scale-like leaves, like those of Cupressus kinds, in pairs or groups of three, and young needle-like leaves not joined at the base.

Old World species

• Juniperus chinensis – Chinese juniper
• Juniperus convallium – Mekong juniper
• Juniperus excelsa – Greek juniper
• Juniperus foetidissima – stinking juniper
• Juniperus indica – Himalayan black juniper
• Juniperus komarovii – Komarov's juniper
• Juniperus phoenicea – Phoenicean juniper
• Juniperus pingii – Ping juniper
• Juniperus procera – East African juniper
• Juniperus procumbens – Ibuki juniper
• Juniperus pseudosabina – Xinjiang juniper
• Juniperus recurva – Himalayan juniper
• Juniperus sabina – Savin juniper
• Juniperus saltuaria – Sichuan juniper
• Juniperus semiglobosa – Himalayan pencil juniper
• Juniperus seravschanica – Pashtun juniper
• Juniperus squamata – flaky juniper
• Juniperus thurifera – Spanish juniper
• Juniperus tibetica – Tibetan juniper

New World species

• Juniperus angosturana – Mexican one-seed juniper
• Juniperus ashei – Ashe juniper
• Juniperus arizonica – redberry juniper, roseberry juniper
• Juniperus barbadensis – West Indies juniper
• Juniperus bermudiana – Bermuda juniper
• Juniperus blancoi – Blanco's juniper
• Juniperus californica – California juniper
• Juniperus coahuilensis – Coahuila juniper
• Juniperus comitana – Comitán juniper
• Juniperus deppeana – alligator juniper
• Juniperus durangensis – Durango juniper
• Juniperus flaccida – Mexican weeping juniper
• Juniperus gamboana – Gamboa juniper
• Juniperus grandis – Sierra juniper
• Juniperus horizontalis – creeping juniper
• Juniperus jaliscana – Jalisco juniper
• Juniperus maritima, syn. Juniperus scopulorum – seaside juniper
• Juniperus monosperma – one-seed juniper
• Juniperus monticola – mountain juniper
• Juniperus occidentalis – western juniper
• Juniperus osteosperma – Utah juniper
• Juniperus pinchotii – Pinchot juniper
• Juniperus saltillensis – Saltillo juniper
• Juniperus scopulorum – Rocky Mountain juniper
• Juniperus standleyi – Standley's juniper
• Juniperus virginiana – eastern juniper, eastern redcedar
  • Juniperus virginiana subsp. silicicola – Southern juniper
• Juniperus zanonii (proposed)

Additional species

As of April 2022^[update], Plants of the World Online lists these extra kinds:

• Juniperus canariensis Guyot & Mathou
• Juniperus coxii A.B.Jacks.
• Juniperus deltoides R.P.Adams
• Juniperus gracilior Pilg.
• Juniperus mairei Lemée & H.Lév.
• Juniperus morrisonicola Hayata
• Juniperus mucronata R.P.Adams
• Juniperus navicularis Gand.
• Juniperus poblana (Martínez) R.P.Adams
• Juniperus polycarpos K.Koch
• Juniperus przewalskii Kom.
• Juniperus saxicola Britton & P.Wilson
• Juniperus taxifolia Hook. & Arn.
• Juniperus tsukusiensis Masam.
• Juniperus turbinata Guss.

Ecology

Junipers can grow in many different places. In the Lahaul valley, they grow in dry, rocky areas. People and animals use these plants a lot, so they are disappearing. Western junipers grow in open woodlands where they get more rain. Without fires or animals eating them, these junipers grow too much and change the environment. This makes it hard for other plants and animals to live there.

Some junipers can get a disease that hurts apple trees. They are also the only food for some caterpillars, including types of moths and butterflies.

Cultivation

Junipers are popular trees and shrubs used in parks and gardens. People have grown them for many years to create many different shapes, colors, and sizes, including very small ones. They are also used in the art of bonsai. Some common types grown include:

• Juniperus chinensis
• Juniperus communis
• Juniperus horizontalis
• Juniperus × pfitzeriana
• Juniperus procumbens
• Juniperus rigida
• Juniperus scopulorum
• Juniperus squamata

Toxicity

In dry places, juniper pollen can float in the air and be breathed into the lungs. This pollen can also irritate the skin and cause a rash. Many people who are allergic to cypress trees can also react to juniper pollen.

Some juniper plants are more likely to cause allergies than others. Plants that have both male and female parts often cause allergies. Plants that are only male also often cause allergies because they release lots of pollen. Plants that are only female usually do not cause allergies because they do not produce pollen.

Uses

Juniper wood is flexible and strong, making it good for building hunting bows in some Native American cultures of the Great Basin. Ancient Mesopotamians used juniper oil to protect against harm. Juniper has been used in traditional medicines, such as by the Dineh (Navajo) people for diabetes. In Scotland, juniper smoke is used in special New Year rites to bless homes.

Juniper berries are a popular spice, especially in gin. They are used to flavor many dishes like quail, pheasant, and venison. They can also be made into a tea or used in Finnish beer called sahti. Juniper wood is dense and rot-resistant, often used for fence posts and firewood. The berries can be distilled to make an essential oil with various natural compounds.