Glosary

A

A

Acicular (= needle-like)

Needle-like leaf, long, thin and generally pointed. These are typical of, for example, pines (gen. Pinus) and cedars (gen. Juniperus and Cedrus, in part), and similar to those of heathers (gene. Erica).

Acuminate

Tapering to a point. May refer to leaves or other parts of a plant.

Alternate (see opposite)

Leaves spaced along a stem with one leaf at each node. Each leaf is on the opposite side of the stem to the previous one.

Apex

Extremity or point of a leaf or other organ.

Appendage

Lobes that appear at the base of the leaf and which are usually differentiated from the other lobes of that leaf (where present), as they are more separated and distinct. This is characteristic of the English oak (Quercus robur L.).

Axillary (see bud)

Located where the leaf stalk joins the stem or branch.

B

Berry

Fleshy fruit surrounded by a thin skin that has juicy pulp inside, such as those of Laurus novocanariensis.

Bipinnate (see pinna and pinnate)

Relating to a leaf formed of several leaflets located on both sides of a main axis (stalk). When this structure is divided, i.e., it is repeated twice, the leaf is bipinnate. This means there is one main axis and then secondary axes which bear the leaflets. It is equivalent to being twice-pinnate. This type of leaf is typical of, for example, many acacias (genus Acacia), the honey locust (Gleditsia triacanthos), and the white cedar (Melia azedarach).

Blade

Broad flat part of the leaf not including the stalk.

Bloom

Waxy covering on leaves, fruits and other organs that gives them an opaque and whitish appearance.

Bud

Small organ or shoot that is normally covered by small, modified, scale-like leaves, from which leaves or flowers develop. It is known as an axillary bud if it is located where the stalk joins the stem or branch.

C

Capsule

Dry fruit that opens when ripe to release the seeds it contains, such as those of the eucalyptuses (genus Eucalyptus), the jacaranda (Jacaranda mimosifolia) and Maytenus canariensis.

Catkins

A group of flowers that normally forms a tight cluster or sprig. They usually hang down and are unisexual (i.e., either male or female) and do not have petals. They are typical, for example, on willows (genus Salix), poplars (genus Populus) and chestnut (genus Castanea) trees.

Compound (see simple)

Relating to a leaf formed by a series of leaflets located around a main axis or stalk. The leaflets do not have an axillary bud at the base of the stalk, this is found at the place the main axis joins, which groups together all the leaflets with the stem or branch.

Cone

False fruit of the conifers (pines, araucarias, etc.) formed of a woody structure with a central axis, around which is a series of scales that enclose the seeds (pine nuts). When the small winged seeds are released, the cones remain on the tree, often throughout the winter.

Crenate

Relating to a leaf whose margin has blunt teeth forming a pattern of small waves. Not to be confused with a leaf blade that is undulating or wavy.

Crown

The upper part of a tree that branches or spreads out.

D

Deciduous

1. (see persistent) Relating to short-lived organs, such as the leaves that many trees lose in the autumn or winter. 2. (see evergreen) Plants that do not keep their leaves throughout the year as they lose them in the autumn or winter.

Dioecious

Describes a species that has separate male and female individuals, like palms (gen. Phoenix, in part), firetrees (Myrica faya and Morella rivas-martinezii), the mastic (Pistacia lentiscus), and the Osage orange (Maclura pomifera).

Drupe

Fleshy fruit containing a stone, like olives.

Dutch elm disease

Dutch elm disease is an illness that affects elm trees (genus Ulmus). It is produced by a fungus from the genus Ophiostoma and is transmitted by bark beetles from the family Scolytinae. In the adult phase these insects drill into the wood to deposit their eggs and leave behind spores of the fungus, which were stuck to their body. These germinate, the fungus grows and collapses the sap-conducting channels, leading to the death of the tree.

E

Egg-shaped (=obovate)

Relating to a leaf shaped like an inverted egg, i.e., with the widest part towards the end.

Elliptical

Relating to a leaf in the shape of an ellipse.

Endemic

Species or subspecies, whose distribution is restricted to a specific geographical area, be that an island, archipelago, province, region, country or continent, and that is not found naturally in any other part of the world.

Entire

Relating to a leaf whose margin is completely smooth, with no teeth, points or other type of breaks.

Established in the wild

A plant that grows in the wild, but which comes from seed of cultivated plant.

Even-pinnate (see odd-pinnate)

Compound leaf with an even number of leaflets that are usually arranged in facing pairs along the main axis or stalk.

Evergreen (see deciduous)

Plants that have green leaves throughout the year, like pines (genus Pinus), holm oaks (Quercus ilex) and laurels (Laurus novocanariensis). This is because they do not lose their old leaves before producing the new ones.

F

Fruit

Structure that in flowering plants (angiosperms) forms from the fertilised flower. It can be dry or fleshy and contains the seeds. In gymnosperms (pines, araucarias, etc.) true fruits are not produced, and the seeds develop within structures known as false fruits, like the cones of pines (genus Pinus) an the galbuli of some junipers (genus Juniperus).

G

Galbulus

Fleshy, rounded false fruit, characteristic of junipers (genus Juniperus). They do not open when ripe and contain a few seeds.

Gall

Tumour-like structure generated by the plant to defend itself from parasitic insects that deposit their eggs in it. The plant reacts and forms a tumour-like mass of tissue around the egg, isolating it and producing the gall. The egg hatches and the larva is protected and surrounded by soft tissue that serves as food and shelter. After metamorphosis, the adult insect makes an exit hole and the gall dries up. These structures are very diverse in form and size. They may appear on the buds, leaves, young shoots and other parts of the plant. They are common, for example, on the Canary laurel (Apollonias barbujana), the willow Salix canariensis, and the mastic (gen. Pistacia, in part).

Gland

Cell or set of cells that accumulate and secrete substances. Some species of stone fruit (gen. Prunus) have a pair of glands on the leaf stalk. For example, the Canary laurel has many small glands located along the main leaf vein. Rhamnus glandulosa and the stinkwood (Ocotea foetens) display more prominent glands at the base of the leaf. Also the tamarisks (gen. Tamarix) have glands like papillae, that accumulate and secrete the salts that the plant absorbs from the ground. Glandulous means 'with glands'.

H

Humid pine forest

Unlike the dry and summit pine forests, this formation occurs under the influence of the trade winds, on the north- and northeast-facing slopes of the islands. Its greater humidity favours the development of the specimens comprising this forest.

I

Inflorescence

A group of flowers. Sometimes the group can appear to be a single flower, although it is in fact formed by several blooms.

Invasive

Referring to a plant that has been voluntarily or involuntarily introduced by humans outside its natural range and which has naturalised, being harmful for native species or others of that region.

L

Lanceolate

Relating to a lance-like or spear-shaped leaf, i.e., elliptical and elongated, narrowing at both ends.

Latex

The milky liquid present in certain plants, like fig trees (Ficus carica), the Canary spurge (Euphorbia mellifera) and the bully tree (Sideroxylon canariense), which can be observed when a leaf or twig is broken off.

Laurel forest

Forest formation very characteristic of the humid zones in the Canary Islands. This forest fundamentally comprises Laurus novocanariensis and other trees like the stinkwood (Ocotea foetens), Persea indica, and the Canary laurel (Apollonias barbujana), among others.

Lauroide (= laurel-like)

Type of leaf that allows plants to regulate excess environmental humidity, enabling them to correctly transpire and respire. The name comes from the laurel tree (Laurus nobilis), which thanks to the waxy layer covering its leaves is able to repel water. They finish in a sharp point that favours the dripping off of liquid.

Leaflet

Each of the leaf-like parts that makes up a compound leaf. They do no have axial buds.

Leathery (=coriaceous)

Relating to a leaf that is strong but flexible, reminiscent of leather, such as those of the holm oak (Quercus ilex), the strawberry tree (Arbutus unedo), the eucalyptus (genus Eucalyptus) and Laurus novocanariensis.

Legume

Dry fruit characteristic of leguminous plants (family Leguminosae). It is formed by two laminae or valves, often elongated, inside which are the seeds.

Linear

Relating to a leaf that very is elongated with quasi-parallel edges.

Lobe/lobed

Rounded, protruding parts on the margin of leaves or other sections of a plant, such as on the leaves of oaks (genus Quercus), fig trees (Ficus carica) and planes (genus Platanus). Not to be confused with a leaf blade which is undulating or wavy.

M

Macaronesian (= from Macaronesia)

Atlantic biogeographical region that includes the archipelagos of the Azores, Madeira, the Savages Islands, the Canary Islands and Cape Verde. According to some authors, it also includes the Moroccan coastal zone.

Margin

Edge or contour of a leaf that can be entire, crenate, toothed, lobed, serrated, sinuous, etc.

Medianías

Canary Island name for the zone of an island between altitudes of 600 and 1500 m; the midslopes. This strip is characterised by having a more temperate and humid climate than the other zones of the islands.

Melliferous

Applied to plants with flowers that contain nectar which bees use to produce honey.

Monteverde

Forest formation that includes within the laurel forest and the Morella-Erica heath.

Morella-Erica heath

Forest formation that is included within the Monteverde forest zone. It isa forest characterised by abundant tree heaths (Erica arborea), firetrees (Myrica faya), and, to a lesser extent, the heather Erica platycodon subsp. platycodon. It is sometimes considered a secondary or impoverished laurel forest formation.

N

Native (see non-native)

A plant that is indigenous to a particular country or region. This does not include plants introduced by humans, whether on purpose or not, or naturalised plants. A plant which is not indigenous is referred to as non-native, i.e., it is not native or indigenous to a particular country or region, but has been introduced or naturalised in that place.

Naturalised

Plant that has been voluntarily or involuntarily introduced by humans outside its natural range and which prospers there as if it were native.

Non-native (see native)

A plant that is not indigenous or native to a particular country or region, which has been introduced by humans, whether on purpose or not, or which has become naturalised in that place. It is the opposite of native.

O

Oblong

Relating to an elongated leaf, that is longer than it is wide.

Odd-pinnate (see even-pinnate)

Compound leaf with an uneven number of leaflets that are usually arranged in facing pairs along the main axis or stalk and finished off by a terminal leaflet.

Opposite (see alternate)

Leaves arranged facing each other along the stem. At each node there is a pair of leaves opposite each other that start at the same point.

Oval

Relating to an oval leaf, or one shaped like an off-centre ellipse.

Ovate

Relating to an oval or egg-shaped leaf, i.e., with the base wider than the end.

P

Palmate

Relating to a leaf shaped like an open hand.

Persistent

The leaves of plants that stay green throughout the year, like pines (genus Pinus) and holm oaks (Quercus ilex). The fact that a tree conserves its foliage during the dry or cold season is the reason the leaves are described as persistent, but this does not mean they are perennial.

Petal

Modified flower leaf that sits over the sepals. It is typically very thin and a different colour to the true leaves.

Pinna (see pinnate and bipinnate)

Division or primary branch of a compound leaf. This is also the name for each leaflet of a compound leaf.

Pinnate (see pinna and bipinnate)

Relating to a compound leaf formed of several leaflets. A pinnate leaf is formed of pinna arranged along both sides of a main axis or stalk.

R

Rachis

Middle or principal vein of compound leaves from which the leaflets arise.

S

Samara

Dry fruit, that does not open when ripe (achene) and which has a membranous wing that facilitates its dispersion by the wind. It is typical of the maples (genus Acer), ashes (genus Fraxinus), elms (genus Ulmus) and tree of heaven (Ailanthus altissima).

Serrated

Relating to a leaf whose margin has inclined teeth like a saw blade.

Simple (see compound)

Relating to a leaf whose blade is not divided into leaflets and which normally has an axillary bud at the base of the stalk, i.e., where the main axis joins the stem or branch.

Sinuous

Relating to a leaf whose margin has shallow waves. Not to be confused with a leaf blade that is undulating or wavy.

Spatulate

Relating to a spoon-shaped leaf, narrow at the base and broadening towards the apex.

Spontaneous (sub-spontaneous)

Plant which becomes established and reproduces without human intervention (i.e., the opposite of a cultivated plant). Not to be confused with native, as naturalised species are spontaneous, but not native. A plant is referred to as sub-spontaneous when it escapes into natural spaces, establishes itself and reproduces without human intervention, giving rise to small, not very viable populations that are not really able to prosper.

Stamen

Each of the elongated elements that form the male organ of a flower. They usually comprise a filament on whose upper part are the anthers, which contain the pollen.

Stipule

Appendage that some leaves have at the base of their stalks.

Suckers

Shoots that arise from the roots of a tree, which damage it by sucking up the sap.

T

Thermophilous forest

Forest formation present on almost all the Canary Islands between altitudes of 350 and 600 m above sea level. This is not a very homogenous community; within it are plant formations dominated by single arboreal species, like endemic olives (Olea cerasiformis), junipers (Juniperus turbinata subsp. canariensis), mastics (Pistacia lentiscus and Pistacia atlantica), and date palms (Phoenix canariensis), as well as, to a lesser degree, dragon trees (gen. Dracaena).

Tomentum

Soft hairs, like felt, that cover the organs of some plants, such as the fruits of the almond tree (Prunus dulcis) and one or both sides of certain leaves.

Toothed (=dentante)

Relating to a leaf whose margin has straight, pointed teeth.

Trade winds

Prevailing winds in the Canary Islands that blow relatively constantly in the summer and less so in the winter, and which originate in the Azores High. Although they start off warm and dry, as they cross the Atlantic Ocean they become humid and cooler. This has an influence on the climate in the Canary Islands.

Turpentine

Almost colourless or amber liquid with a characteristic scent that is obtained by distilling the resin of various coniferous species and other aromatic plants. It is used as a paint solvent, a raw material for making synthetic aromatic compound, and in some disinfectants.

U

Underside (see upper side)

Lower face of a leaf, that is generally paler than the upper face or upper side.

Undulating

Relating to a leaf whose blade is not flat but which has a wavy surface. Not to be confused with a sinuous, crenate or lobed leaf margin. Beech leaves are usually undulating.

Upper side (see underside)

Upper face of a leaf that is generally brighter coloured than the lower face or underside.

V

Valve

Each of the parts into which certain fruit are divided, such as legumes (family Leguminosae).