volume of timber. It reaches a height of 80 feet and girths of 12 feet
are common. A girth of 26 feet combined with a 40 feet bole has been
measured. It has a gregarious habit similar to _Khaya senegalensis_ on
the edges of “fadammas” and in flat country where water lies during the
rainy season. Hundreds of saplings may be found round these clumps. It
is most readily distinguished from other species, at a distance, by
the straight, light-grey stem, which is generally tapering in form,
and by the shape of its crown which is triangular with a flat top. The
crown is dense and dark, the limbs at an angle of about 30 degrees to
the bole and the bulk of the foliage being on the summit. The bole is
generally swollen at the base. It is a very fast growing species.
=The Bark= is very light in colour, this being emphasised at a
distance. It is rough with large even-sized scales. The bark of
saplings, owing to the annual fires, is very thick and scaly, cracking
in horizontal rings round the stem. This forms a highly protective
covering. An oleo-resin, or balsam, exudes from the slash, which is
dark crimson with small white streaks.
=The Wood=, of which a great volume is yielded by the tree, is
red-brown with darker streaks. In transverse section the rings
are fairly well defined dark, regular lines, the pores are large,
mostly single, widely and fairly evenly distributed, the rays fine,
continuous, unevenly spaced but 3 to 4 to each pore, bending in
a curious manner where they cross the lines of soft tissue, just
visible with the naked eye. In radial section the rays are small
light-reflecting bands and in the tangential section are clearly
visible as fine ripples. The sapwood is whitish with a faint brown or
pinkish tinge, and the rays are very clearly marked on the two vertical
sections. This is a very good light-weight timber, very easily worked
and not very durable or strong, but its large sizes, soundness and
appearance enhance its value. It has a most pleasant cedar-wood smell.
Weight 44 lbs. a cubic foot.
=The Leaves= are 18 inches long, pinnate with some 6 pairs of large,
pointed, dark-green, shiny leaflets. The young leaves are soft and pink
in colour.
=The Flowers= are conspicuous, chiefly at the top of the tree, in
large, flat panicles, in December. The flowers stand erect on the
horizontal panicle and consist of a 5-lobed, imbricate calyx, one
sepal being smaller than the others, greenish-white in colour; 10
white stamens, 2 inches long and a long, white pistil which swells to
form the seed-pod. The flower parts are borne on a stout club-shaped
receptacle.
=The Fruit= is a flat pod, about 3 inches long and 2 inches wide,
whitish in colour. It splits by the curling up of the inner layers and
frees one oval, flat, dark-brown seed, the rudiments of 3 or 4 others
being visible attached to the suture. The open pods with large brown
seeds hanging from their edges are a conspicuous feature in masses
on the tree tops, the seeds and pods remaining some time in position
before being blown down.
=Uses.=—The timber is made into planks, mortars, canoes and
cattle-troughs. The resin is burnt in houses as a fumigating incense.
In times of extreme famine, the young leaves are appreciated as a
vegetable, being eaten with the addition of salt and pepper.
[Illustration]
=PARINARIUM CURATELLAEFOLIUM= Planch.—_Rura, Gwanja kusa_. ROSACEAE.
A small and very common tree averaging 15-20 feet high with a girth of
1-2 feet. It has no form or special characteristic of growth, being
similar to the many other species with which it occurs in open savannah
forests. Its only importance lies in its occurrence in large quantities
over considerable areas. It is readily distinguished from other species
by its flowers and fruits, which latter may be seen for several months
in the year.
=The Bark= is very dark, sometimes almost black, with small, prominent,
corky scales up to 1 inch square. The slash is a dull, dark red.
=The Wood= is light brown, with a slight orange tinge. In transverse
section the rings show as slightly darker lines, the pores are small,
oval, with their length radial, single, not numerous, and connected
by continuous waved concentric lines of soft tissue. The rays are
extremely fine and very close together, quite invisible to the naked
eye. In vertical section the pores are open and slightly darker, the
grain close. It is a soft, sound wood, easily worked, planing with a
dull, smooth finish, not picking up much. The weight is 48 lbs. a cubic
foot.
=The Leaves= are about 5 inches long and 2½ inches broad. They are
alternate, pale green and smooth above and greyish beneath.
=The Flowers= are in long, dense or open, terminal panicles, a number
together. They are greenish in colour, the whole panicle covered with
a light pubescence. Each flower consists of a grey-green, 5-pointed
calyx, 5 minute white petals and 10 stamens, some with pink anthers.
They appear about December or January, and are conspicuous by their
numbers on the leafless tree.
=The Fruits= are reddish-brown drupes, about an inch long, the skin
covered with a number of small, grey lenticels. They have a reddish,
sweet, edible flesh and a large, hard stone. They ripen towards the end
of the year and are the readiest means of identification of the species.
=Uses.=—The fruits are eaten fresh.
The young trees are cut for poles for building (gofa).
[Illustration]
=PARINARIUM MACROPHYLLUM= Sabine.—_Gawasa_. “_Ginger-Bread Plum_.”
ROSACEAE.
A common tree locally in parts of the more northerly provinces. It is
not found distributed evenly through the forests but in numbers over
small areas here and there. It is very highly valued by the native for
its fresh fruit and protected on farm lands. It is a thick-set, squat
tree with a short, heavy stem and wide-spreading, crooked branches
forming a round or flat crown. It is from 15-25 feet high, sometimes
more, with a girth up to 8 feet. The foliage, owing to the size of
the leaves, is dense. It is somewhat similar to its congener, _P.
curatellaefolium_, but the leaves are larger, the flowers heavier and
the whole tree on a larger scale. It grows in dry, sandy soils.
=The Bark= is grey and not rough, covered with small even-sized scales.
=The Wood= is a light brown colour, frequently with large grey
discolorations darkening the colour. In transverse section the rings
are obscure bands, the pores are small, few and distributed rather
unevenly, single, connected by very faintly marked and poorly developed
soft tissue lines. The rays are exceedingly fine and very close
together. In vertical section the pores are few and fine and the grain
is close. It is a fairly hard wood, sawing well and planing with little
picking up to a hard, smooth finish which polishes well. Weight 45 lbs.
a cubic foot.
=The Leaves= are some 5 inches long and 3-4 inches wide on the average,
but may be as much as 8 inches long and 5 inches wide, with a stout
stalk not above ¼ inch long. They are slightly cordate at the base and
broad at the tip with a small point. There are some 15-20 straight
veins on each side of the mid-rib, sunken on the upper surface and very
prominent on the underneath. The upper surface is a brilliant light
green gradually darkening with age, the under side grey. There is a
dusty brown covering of hairs on the upper surface, which rubs off
readily in the hand and exposes the smooth green surface. The stalk is
densely covered with brown hairs.
=The Flowers= are in terminal racemes from 3-9 inches long, all parts
except the petals covered with the hairs. Each flower has a 5-lobed
calyx, 5 white petals in 2 groups of 3 and 2, 10-20 white stamens
with yellow anthers and a curved, white pistil. The flower in bud is
enclosed in 2 bracts which are pushed up by expansion of the flower and
then fall off the end. The flowers are found on the tree every month of
the year, a continual succession of flowers and fruit occurring.
=The Fruits=, which are found all the year round, are plums,
reddish-brown with an orange tint, rounded or oblong, 1½-2 inches
long and 1-1½ inches broad, the surface roughened with numerous grey
lenticels. The sweet, edible flesh is whitish, moist and mealy, about
½ inch thick round the very tough, thick stone which has one or two
“kernels.” The ripe fruit has a sickly sweet smell.
=Uses.=—The wood of large specimens makes very good mortars.
The fruits are highly appreciated and eaten fresh. They are brought to
the big towns from long distances in some places and will sell for as
much as a penny each in the markets.
[Illustration]
=PARKIA FILICOIDEA= Welw.—_Dorowa_. “_Locust Bean Tree_.” LEGUMINOSAE.
This is the type tree of the Park formations and a very common and
well-known species with a wide distribution. Owing to its great value
as a food and its uses by the natives, it is often the sole occupant
of extensive areas of cultivation. It grows to large sizes, 50-60 feet
high with girths of 10 feet or more. The bole, in the case of trees
which are grown in the open, is short, not, as a rule, above 10 or 12
feet, and several large, spreading limbs form a very wide crown which
appears dark and dense at a distance, but which, in fact, gives only
average shade. There are small, rounded root-flanges. All trees near
habitation are owned by the individual. Those in the forests have a
different habit of growth, the bole being longer, the branches more
erect and the crown less spreading. The large crowns of the park trees
are generally due to the cutting of the branches for fuel. _See_
USES. The tree pollards well and shoots readily from the stool. It is
liable to attack from white ants when young, and to the ravages of
caterpillars which may completely defoliate the tree.
=The Bark= is dark brown or dull grey, with small, regular scales of
varying roughness. The branches and the stems of young trees are a
light grey, almost silvery, and smooth. The bark at the base of the
tree is often much chipped about by the natives who make an infusion
of it, drunk as a tonic. The slash is brick red, spongy and fibrous in
thin layer formation.
=The Wood.= The heartwood is a dull brown colour, the sapwood a dirty
yellow. Even the largest stems, 3-4 feet in diameter, cut in the north,
show none of this heartwood. In transverse section the rings are faint
and wide apart, the pores are large, open, fairly regularly distributed
in the well-marked soft tissue festoons, with nests of 3 or 4 here and
there. The rays are straight, continuous, evenly spaced, not all the
same thickness, and show as long, light-reflecting bands in radial
section. In vertical section the grain is fairly open, the hard and
soft tissue giving a mottled appearance in tangential section. The wood
is most easily worked with all tools, planes with a dull finish and
though liable to crack a little is on the whole a sound, though weak,
timber. The weight is only 32 lbs. a cubic foot.
=The Leaves= are bipinnate, 15-18 inches long, with opposite, pinnate
leaflets bearing numerous dark green pinnules, oblique, ¾ inch long,
alternate but nearly opposite towards the tip. They have a shining
surface, and the young leaf is reddish.
=The Flowers= are pendulous balls some 2½ inches in diameter on a 7
inch stalk. They appear in March before the new leaves or with them
and are dark red in colour and sweet-scented. They consist of 10 long,
red stamens with black anthers and a simple style, in a 5-lobed calyx
with honey glands. The flowers are visited both by bees and flies.
Called “tutu” by the native, boys suck the balls for the honey. The
flower-buds are called “gundar tutu.”
=The Fruit= is a bean, some 9 inches long, dark brown in colour, in
pendulous clusters on the tree in July. When young they are called
“sabada”; when brown, but before ripening, they are called “garda.” The
ripe seeds are black and embedded in a yellow, mealy pulp. They are of
great value as an annual food-crop.
=Uses.=—The timber is used for making mortars and basins. The seeds are
fermented and made into cakes called “daudawa.”
The husks are soaked in water till fermentation takes place and the
resulting liquid spread over earth floors and on the walls of dye-pits
to bind the surface. The liquid is called “makuba” and is also used as
a fish poison.
The branches are cut for fuel for the boiling of the water used in the
purification of women after child-birth.
The mealy pulp round the seeds (garin dorowa) is used in soup.
An infusion of the bark is a tonic.
[Illustration]
=PARKINSONIA ACULEATA= Linn.—_Sasabani, Sharan labbi_. “_Jerusalem
Thorn_.” LEGUMINOSAE.
A small exotic tree introduced by Arabs and planted in most of the
Northern towns to such an extent that it is worthy of inclusion here.
It is a delicate and graceful shrub-like tree up to 25 feet high. It
has a single stem branched a foot or two above ground level; in some
cases there is a stem over 6 feet in length before the branches, erect,
with their ends spreading out and drooping down, occur. It grows best
in an open position and does not thrive in the shade, where it grows
very weak and straggling, without the vivid green of trees in the open.
=The Bark= is bright green and smooth.
=The Thorns= are straight and sharp, ¼ inch long, light red in colour
with thickened, fleshy green bases from which spring the leaves. The
scars of fallen leaves can be seen on this thickened base.
=The Leaves= are bipinnate with one or two pairs of pinnae which
consist of a broad, flat mid-rib some 9 inches long from which little
oval leaflets under ¼ inch long spring alternately. These are sensitive
and at night, or when gathered, fold inwards and lie flat on the
mid-rib. The rib and leaflets are dark green and smooth.
=The Flowers= are in pendulous, sparse spikes amongst the leaves. Each
is an inch in diameter and has 5 pale green sepals, 5 crinkly yellow
petals, one of which is more prominent than the rest and forms a throat
covered with small red spots. There are 10 short stamens with red
anthers and a short brown pistil. The flowers are found most months of
the year.
=The Fruits= are jointed pods, varying in length according as they
contain 1-6 seeds, the longest being 6-7 inches long. They are jointed,
light brown and veined, and when ripe are very light and brittle. The
seeds are ⅓ inch long, black, oval, round in cross section, very hard
and smooth and rattling loose in the pod. They may be found for some
months in the year, particularly in February.
=Uses.=—Ornamental and shade providing.
[Illustration]
=PROSOPIS OBLONGA= Benth.—_Kiriya_. LEGUMINOSAE.
A large tree attaining a height of over 60 feet with girths of 6-7
feet. In good forest it may have a bole length of 30 feet, but in the
open savannahs it is branched to within a few feet of the ground, as a
rule, and its crooked limbs form an irregular, rather open crown. The
finer twigs droop considerably and the tree may bear some resemblance
to _Tamarindus_. In old trees in good forest there is a high, wide
crown, open, and giving little shade. There are small rounded root
flanges. The features which most readily distinguish it are its bark,
colour of foliage and pods, q.v. It likes good, open soils.
=The Bark= is almost black, with ragged, crisp, curling scales which
are concave on the outer surface and leave light brown patches where
they fall. Sometimes the bark has a bluish tint. That of the smaller
branches is light grey or brownish and smooth. The slash is reddish,
darkening to orange and red-brown.
=The Wood= is a rich red brown. The sapwood is grey. In transverse
section the rings are indistinct, the pores are open, regularly
distributed, mostly single, a few double. The rays are very fine, waved
and unevenly spaced, not visible to the naked eye. In vertical section
the pores are seen to have dark resin contents, the grain is open, and
there are bands of colour, the lighter soft wood picking up and the
darker hard tissue planing smooth, according to direction of planing.
There is a marked reflection of light from these bands. It blunts axes,
is hard to saw, must be finished with glass-paper after planing, when a
fine surface is obtained, oily to the touch. It will not take nails. A
very tough, strong, durable timber. Weight 65 lbs. a cubic foot.
=The Leaves= are bipinnate with 2-4 opposite pairs of pinnae each
bearing some 6-10 leaflets ¾-1 inch long and ¼ inch or more wide, with
a pointed tip and the rib not in the middle. They are light green and
softly pubescent. The pairs are inclined to the top side of the main
stalk and between each pair of pinnae there is a little gland. The base
of the stalks is much enlarged.
=The Flowers= are in short pedunculate spikes, the latter 1½-2½ inches
long and densely composed of small yellowish flowers, which appear in
May. Each flower has a 5-lobed calyx, 10 stamens with yellow anthers
and a short hairy pistil. The flowers are sweet-scented.
=The Fruits= are large pods from 4-6 inches long and an inch in
diameter, slightly flattened in one direction, pointed at the tip, a
dark, purple-brown colour. The hard, shiny, brown seeds, oval and ⅓
inch long, are embedded in a dry, cream-coloured, spongy-looking pulp,
each separated from the other by a thin, transparent membrane. The
seeds rattle loose in the pod. The pods are very persistent on the tree.
=Uses.=—The natives use the wood for tool handles and burn it for
charcoal, the quality of which is very fine and much valued by
blacksmiths.
The wood is also used for making pestles for large mortars and the
manufacture of tobacco pipes.
[Illustration]
=PSEUDOCEDRELA KOTSCHYI= Harms.—_Tuna(s)_. MELIACEAE.
This species, which is closely allied to the mahoganies (_Khaya_), is
a large and valuable timber tree and occurs particularly in groups,
or singly here and there in the Tree savannah. It is a handsome tree,
regular in shape, with a straight stem and a bole of often 20 feet
in length with a girth of 5 or 6 feet. The total height may be 40
feet. It is rather slow growing and though the crown is fairly dense,
is essentially light-demanding and not much of a soil-improving
species. It can be seen reproducing itself from root-suckers and very
rarely from seed, since the latter is destroyed by fire. The crown is
cylindrical and regular and the limbs ascend vertically.
=The Bark= is very conspicuous by its light grey, almost silvery,
colour. It is regularly fissured and the scales are of equal size and
soft and thick. The base of the stem is often swollen and the bark
charred by repeated firing. The slash is bright crimson and shows a
layer formation.
=The Wood= is a red-brown colour, flecked with black and dark brown
of a most distinctive pattern, rather open grained, scented, hard and
weighs 50 lbs. a cubic foot. It carpenters well and polishes. The pores
are small and open, scattered rather thinly along and between the rays
which are long and evenly spaced and straight. A useful and ornamental
wood if large sizes could be obtained.
=The Leaves= are pinnate, about 1 foot long with 4 or 5 pairs of
leaflets which have wavy edges so that the leaf resembles that of the
oak. The leaflets may be opposite or not and a terminal leaflet is not
always in evidence. In colour the leaf is dark and shiny on the upper
surface and soft and grey with rough venation beneath. They are in a
rosette-like formation like the mahoganies.
=The Flowers= are in panicles in the axils of the end leaves and are
white and sweet-scented. Each is about ¼ inch across, with 5 petals, a
knobbed pistil and 10 stamens whose filaments are united and surround
the pistil. They appear in February.
=The Fruits=, which ripen in February of the following year, are
capsules about 4 inches long, shaped like a club and standing erect.
They are brown in colour and split from the apex into five sections
which curl back and release the seeds. These are packed, about six in
each section, round a pith centre, the wings, 1¼ inches long, pointing
downwards, one over the other. The split capsule remains some time
on the tree after the seeds have fallen. The capsules are very few
in number on a tree considering the enormous number of flowers which
bloom, but are very conspicuous and a ready means of identification.
The mahogany coloured seeds will blow 200 yards away.
=Uses.=—An infusion of the bark is used as a cure for digestive
trouble. The timber is used for furnishings and is an excellent wood
for all articles, owing to its being so easy to work.
[Illustration]
=PSOROSPERMUM SENEGALENSE= Spach.—_Kashekaji_. _Kaskawami_.
HYPERICACEAE.
A common shrub in the Bush savannahs, not extending very far north, but
abundant in secondary growth after cultivation. It is common amongst
the rocks on the Bauchi plateau almost up to the 4,000 feet level. It
is equally common all through Zaria and S. Sokoto, in fact, anywhere
up to 12° N. It forms a large, compact, round shrub some 15 feet high
with dense foliage, generally on a single, low-branched stem. The
distinguishing character is the rusty-coloured underside of the hairy
leaves.
=The Bark= is light brown and has small corky ridges and fissures.
=The Leaves= are from 3-5 inches long and 1½-2½ inches broad, in pairs,
ovate, with wavy margins, tapering tips, very short stalks, downy on
both surfaces, that on the upper surface rubbing off to expose a light,
shiny green. The under surface is densely covered with rust-coloured
down, readily rubbed off and exposing a fine network of veins with a
minute black dot in almost every cell and a pronounced row of dots all
round the margin. The mid-rib is recurved causing the leaf to fold up
along it. The shoots are covered with orange-coloured hairs.
=The Flowers= are in dense clusters 3-4 inches in diameter, from
January onwards. Each is ¼ inch across, has a 5-pointed calyx with
vertical purple lines on the inside, 5 white petals densely covered
with white hairs, 5 columns of stamens with some 9 anthers each and a
pistil with 5 lobes each with a globular stigma, shining brown.
=The Fruits= are capsules with 5 cells, one generally maturing at the
expense of the rest. They are a little over ¼ inch in diameter, purple,
shiny and fleshy. The sepals clasp them close, and the stigma remains
are persistent.
=Uses.=—A concoction of the leaves and bark is applied for skin
diseases.
[Illustration]
=PTEROCARPUS ERINACEUS= Poir.—_Madobia_. LEGUMINOSAE.
A medium-sized tree of the savannahs, averaging some 40 feet in height
with a girth of 4-6 feet. Timber producing examples considerably
larger are common enough and good, clean, straight boles 20 feet or
more in length are found. It has a wide distribution up to 14° N., but
is a small tree at this latitude. The crown is high, open, wide and
rounded, not giving much shade. Larger examples have short buttresses.
The species is susceptible to fire which hollows the stems. The long
pinnate leaves, masses of yellow flowers and winged, hairy seeds on
the leafless tree are characteristic features. Over many miles of the
better types of savannah it is the type tree amongst others and occurs
in quantities.
=The Bark= is very dark and rough with scales which curl up at the ends
and make the bole appear shaggy. The scales fall in pieces 3-4 inches
long. The bark of the branches is light grey and smooth. The slash is
brown with fine red lines and a blood-red resin exudes from it.
=The Wood= is a rose-red or rich brown colour with a wavy grain of
darker streaks. It might almost be called figured, especially in
tangential section. In transverse section the pores are small, single
and scattered and connected by fine, wavy lines of soft tissue; the
rays are extremely fine and closely spaced, not visible to the unaided
eye, and the rings are indistinctly marked darker lines, generally
varying in width apart and rarely concentric. The radial section has
a marked banding of dark and light. The wood is hard, liable to split
in seasoning, difficult to saw and the planed surface smooth, slightly
oily and taking a high polish. The weight is 60 lbs. a cubic foot.
=The Leaves= are pinnate, a foot long, with some 11-13 pinnae,
alternate, and wide apart. The upper surface is shiny, the lower
grey-green, the mid-rib prominent beneath and grooved above. The leaves
are pendulous.