The 'allon' (also called 'elon') mentioned in the Old Testament, is thought to be the oak (in fact, 'allon' is the Modern Hebrew word for the oak). Allon means strong and mighty while the word El is the Hebrew name of God. The oak fits this meaning well, as it is considered a strong tree.

There are five species of oak found in Israel.
i. Palestine oak or common oak (Quercus calliprinos)
ii. Tabor oak (Quercus ithaburensis), also called the Valonia oak (Quercus aegilops)
iii. Kermes oak (Quercus coccifera)
iv. Boissier oak, also called tola oak (Quercus boissieri)
v. Cork oak (Quercus suber)

Palestine oak

A Palestine oak. PICTURE: Davidbena (licensed under CC BY-SA 4.0)

The two most widespread species of the oak are the common oak and the Tabor oak, but the kermes oak is the most abundant oak found in Israel, growing on its rocky hills. The common oak, cork oak and the kermes oak are evergreens, while the Tabor oak and boissier oak are all deciduous.

The Palestine or common oak (Quercus calliprinos) is an evergreen oak. It is a small to medium-sized tree which can grow up to 18 metres tall, but is often much smaller. It can be found in the valleys and the hills of Judea and Galilee. It has spiny-serrated leaves that grow up to five centimetres in length. The acorns grow between three to four centimetres long and have a diameter of two to three centimetres.

"The two most widespread species of the oak are the common oak and the Tabor oak, but the kermes oak is the most abundant oak found in Israel, growing on its rocky hills. The common oak, cork oak and the kermes oak are evergreens, while the Tabor oak and boissier oak are all deciduous."

The Tabor oak (Quercus ithaburensis) is a stately deciduous tree. Although in the warmer part of the country, such as the upper Jordan River the leaves may persist throughout winter. It varies in height from 10 up to 25 metres tall and can have a 20 metre crown perimeter. It is usually noticed because of its well-developed trunk. It is often up to five metres in height before it branches. It does not like cold winters so it only grows in lower altitudes and is found in areas such as the Sharon, Lower Galilee, the Hulah and the Dan Valleys. The leaves of the Tabor oak are glossy green above and grey underneath. They are oval in shape, between four to nine centimetres long and usually have 7 to 10 pairs of teeth along the edges. However these teeth are not sharp like the Palestine oak. This tree bears huge acorns.

The kermes oak (Quercus coccifera) of the western Mediterranean, is closely related to the Palestine oak (Quercus calliprinos), indeed it is treated as a subspecies or variety of it by some botanists. The kermes oak is distinguished from the Palestine oak by its smaller size. It is a shrubby tree usually growing only between four to six metres high, but occasionally will grow up to 10 metres. It is a prickly evergreen oak which branches out at the base. It is thickly covered with leaves and produces abundant acorns. Sometimes the kermes oak is identified as the elah.

The boissier oak, also called the tola oak (Quercus boissieri), is known in Hebrew as Allon Hatola. The name tola comes from the name of the crimson worm (coccus ilicis) which is called tola in Hebrew. This worm (more accurately a scale insect) lives off the branches of this tree (as it does off the Tabor oak). It produces the colour scarlet which was used as a dye in the curtains of the tabernacle and on the High Priest’s garments. The boissier oak has a tall straight trunk and is deciduous. It has elongated acorns which are both thinner and longer than other species of oak in Israel. They grow up to four centimetres long. The boissier oak usually grows above 800 metres and it is found in the hill country of the Golan, Mount Hermon, Galilee, Mount Carmel, and the Samaria and the Judean hill country.

The cork oak (Quercus suber) is an evergreen oak which grows to about 20 metres in height. Its leaves are between three to seven centimetres in length and its acorns are around two to three centimetres long. They are oval or oblong in shape. This tree is found in the dense scrub lands of the Mediterranean coast and in forest areas further inland.

There are a number of references to the allon in the Old Testament. Genesis 35:8 records how Deborah (Rebekah’s nurse) was buried under an allon tree. The place was known as Allon Baccut, which literally means ‘oak of weeping’.

Writing in 1992, English botanist Nigel Hepper made the comment that "the practice of marking graves with oak and terebinth trees is still continued to this day and several fine evergreen oaks may be seen, for example beside the road from Jerusalem to the coast". 
The oak woods of Bashan are mentioned a couple of times in the Old Testament including by the prophet Isaiah:
 "The Lord Almighty has a day in store
for all the proud and lofty,
for all that is exalted
(and they will be humbled),
for all the cedars of Lebanon, tall and lofty,
and all the allon [oaks] of Bashan,
for all the towering mountains
and all the high hills,
for every lofty tower
and every fortified wall,
for every trading ship
and every stately vessel.
The arrogance of man will be brought low
and the pride of men humbled."
 - Isaiah 2:12-17

Zechariah also mentions the oaks of Bashan when they existed as a dense forest:
"Open your doors, O Lebanon,
so that fire may devour your cedars!
Wail, O pine tree, for the cedar has fallen;
the stately trees are ruined!
Wail, allon [oaks] of Bashan;
the dense forest has been cut down!

“Listen to the wail of the shepherds;
their rich pastures are destroyed!
Listen to the roar of the lions;
the lush thicket of the Jordan is ruined!"
- Zechariah 11:1-2

Allon timber from Bashan was used to make oars as recorded in Ezekial 27:6: "They made all your timbers of pine trees from Senir; they took a erez [cedar] from Lebanon to make a mast for you. Of allon [oaks] from Bashan they made your oars; of cypress wood from the coasts of Cyprus they made your deck, inlaid with ivory."

God, through the prophet Isaiah, makes a promise concerning the punishment of Judah with respect to the allon. He says that even though there will only be a stump of an allon left, yet they will sprout again: 
Then I said, 'For how long, O Lord?' And He answered: 'Until the cities lie ruined and without inhabitant, until the houses are left deserted and the fields ruined and ravaged, until the LORD has sent everyone far away and the land is utterly forsaken. And though a tenth remains in the land, it will again be laid waste. But as the terebinth [elah] and allon [oak] leave stumps when they are cut down, so the holy seed will be the stump in the land." - Isaiah 6:11-13

Allon timber, like that from other trees, was used for making idols as recorded in Isaiah 44:14-15: "He cut down cedars [erez], or perhaps took a cypress [tirzah] or allon [oak]. He let it grow among the trees of the forest, or planted a pine [oren], and the rain made it grow...he also fashions a god and worships it; he makes an idol and bows down to it."

People made sacrifices under allon trees as recorded in Hosea 4:13:
"They sacrifice on the mountaintops
and burn offerings on the hills,
under allon [oak], poplar [livneh] and terebinth [elah],
where the shade is pleasant.
Therefore your daughters turn to prostitution
and your daughters-in-law to adultery."

The allon was a tree of strength. Amos 2:9 says: "I destroyed the Amorite before them, though he was tall as the cedars [erez] and strong as the allon [oaks]. I destroyed his fruit above and his roots below." 

That the allon was an important and noticeable tree is seen in Joshua 19:33 where the allon was used as a marker for the boundary of the tribal area of Naphtali: "The sixth lot came out for Naphtali, clan by clan: Their boundary went from Heleph and the allon [large] tree in Zaanannim, passing Adami Nekeb and Jabneel to Lakkum and ending at the Jordan". Specifically this allon may have been the Tabor oak, because of its stately appearance."

Finally oaks were useful in other respects. They were one of the sources of tannin. Tannin was necessary for tanning hides. Tanning is mentioned in Acts 10:6, where one Simon the tanner lived by the coast at Joppa.

This is an edited excerpt from Alvin Johnson's iBook 'Biblical Flora', 2017. The book is available for free download on iTunes. A teacher's edition is also available for purchase.