Mint

Mentha spicata (Green Mint) is a low, creeping and rather invasive plant that is indispensable in a fragrant border. Mentha spicata blooms with small pale purple or pink flowers. It easily grows widely on all soil types and will certainly have to be kept under control. It is an herb with numerous uses, both kitchen use and medicinal. On the photo you can see covering hairs and glandular trichomes from which the typical aromatic substances are excreted.

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Primitive, but unique

Ferns are perhaps very old plants, but they are unique in their kind. They already occur in several hundred million year old fossils. After all, it was the first plant with roots and a real vascular system. In this way the ferns managed to extract water from the ground and use it for their further development. Because of the branches of the vessels it was also possible to get the water into the tops of the feathers or leaves. Ferns do not carry flowers. They therefore do not propagate with seeds, caused by fertilization of pistils with pollen through bees, beetles, birds, wind or otherwise. 

Inverted but also ‘upright’

The photos show a cross section of a leaf stalk or petiole of the mahogany tree. A Motic inverted microscope with a fluorescence attachment is used for this. The attachment is equipped with a DAPI long pass filter (excitation at 375 nm).

Large cattail

Typha latifolia, called ‘large cattail’ in English, is a water plant that is mainly found in eutrophic and acid water, along the shores of ponds, ditches and in swamps. This perennial has an upward and wide-spread growth habit. It is easy proliferating through rhizomes. If planted in a garden pond, locking it in a good pond basket is the message. The leaves are broad, linear and blue-green colored. Large cattail blooms from June to September with double cigar-shaped ears. The male ears are at the top, the female right below. After wind fertilization, the characteristic brown colored ‘cigars' form the female flowers. The seeds of cattail develop from the flowers on the cigars. The seed fluff is normally transported by the wind. The plant is hardy, endures sea breeze, air pollution and has a beautiful winter silhouette.

 

Protected against harsh conditions

Helm grass is what we encounter in the dunes among others in the Netherlands. The Ammophillia arenaria can withstand the salty water and salty sea air. Ammophillia arenaria can be planted on all types of soil, only on clay soil it is best to make the soil poor with masonry sand. The soil must be calcareous.

A pest on grapes

Uncinula necator or powdery mildew, a basidiomycete, is a pest on grapes. Its septate hyphae forms a mycelium on the surface of the leaves similar to a spider web. Special hyphal branches, the haustoria, penetrate the host cells to absorb food substances, thereby weakening the grape and reducing the harvest.

Yellow, widespread and strong

Xanthoria parietina is a yellowy orange colored leafy lichen that is one of the most common species around. The yellow chemical xanthorin is thought to be produced as a defense against UV radiation to which it is exposed in its normal habitat like cement tiled roofs, exposed twigs and branches etc.

Cleverly adapted to the amount of light

In addition to water, carbon dioxide, mineral salts, and heat, light is one of the factors which are of vital importance for the green plant. It provides energy for the photosynthesis and brings about the growth and development of plant forms. In addition to the light on itself, also the light intensity plays an important role. The leaves of deciduous trees are the place where the energy required for the plant is formed by photosynthesis and assimilation. This is done in the chlorophyll-containing cells of the palisade layer. There below is loose fill and aerenchyma tissue. Outwardly a leaf is sealed off by a layer of epidermal cells, the outer walls thereof are thickened.


In fact, the light influences the construction of the plant and its leaves. We find sun leaves on the outer edge of the crown and on the south side of it, shade leaves

How to be heat and drought resistant?

The Oleander has big, red, white or yellow, highly fragrant flowers. The 7 - 8 m high shrubs are spread from the Mediterranean to East Asia, growing in sunny locations and near watercourses. In North West Europe it is often drawn as a container plant.

Its leathery, lance-shaped leaves show the characteristics of xeromorphic - that means drought resistant - sun plants. Oleander is adapted to the very hot and dry borders of watercourses in summer.