Sunday 20 March 2016

Rottboellia cochinchinensis

Rottboellia cochinchinensis itchgrass, pricklegrass, guinea fowl grass

Here is a real nasty emerging weed which I have noticed popping up all along the KwaZulu-Natal north coast. Watch out for it eradicate as soon as it is discovered before it gets out of hand.

A quick search on the internet turned up the following information about Rottboellia cochinchinensis

Rottboellia cochinchinensis

Distribution
A native of Indo-China, which has naturalised throughout the tropics of Asia, in north-eastern Australia and the savannah zones of Africa including South Africa.
Rottboellia cochinchinensis has been introduced throughout the Caribbean, Tropical America and the southeastern and central United States. Although it may occur under a variety of moisture, light and soil conditions, at a wide range of altitudes, Rottboellia cochinchinensis is most commonly found on sunny, disturbed sites with high rainfall or irrigation in subtropical and tropical climates.

Distinguishing Characteristics
Rottboellia cochinchinensis is an erect, annual grass that can grow to 3m high. Stilt roots often develop at the base of the stem. Plants produce abundant side shoots and grow into large clumps. The leaf sheath and the lower portion of the leaf blade are usually covered with stiff hairs that have a small swelling (tubercle) at the base. 



These hairs break off on contact, penetrating and irritating the skin. The leaf blades, which measure 150mm to 500mm inches long and up to 25mm wide, typically have broad white midribs and scabrous (rough to the touch) margins.


The ligule is a membranous, ciliate flap, to 3mm long. The slender, cylindrical, unbranched inflorescence is segmented. Each heteromorphic segment consists of two types of spikelets:  a sessile (stalkless), fertile spikelet that is embedded in the axis of the inflorescence and a pedicellate (stalked), often sterile spikelet with the pedicel fused to the internode of the inflorescence axis. The spikelets are awnless, narrowly ovate to triangular in shape, and somewhat flattened. 


At maturity, the seedhead breaks into segments, with the paired spikelets attached. A small, cylindrical gland-like projection, known as an elaiosome, is located at the base of each segment. Rich in lipids and proteins, the elaiosome attracts ants that help to disperse the seed.



Environmental  and Economic impact
Rottboellia cochinchinensis is an invasive aggressive weed under various ecological conditions, in at least 18 crops in 44 countries. It is estimated that more than 3.5 million ha of cropping lands are infested with Rottboellia cochinchinensis in Central America and the Caribbean
Rottboellia cochinchinensisis a serious weed of cotton in Zambia and Zimbabwe and a moderate weed of cotton in Ethiopia, Mozambique, Sudan, Uganda and Venezuela; a serious weed which effects on crop yield,
It competes for soil nutrients, water and light, resulting in reduced crop yields, and also hosts insect pests and diseases that affect graminaceous crops.
Under optimal conditions, Rottboellia cochinchinensis plants may begin producing seed six to seven weeks from emergence and continue to produce seed throughout the growing season. A single plant can yield between 2,000 and 16,000 seeds.
Recent research (Meksawat and Pornprom 2010) has shown that Rottboellia cochinchinensis is allelopathic releasing contains chemicals that inhibit the germination and growth of nearby plants.
The irritating hairs on the leaf sheaths discourage foraging by livestock and wild herbivores.

Rottboellia cochinchinensisis a problem to labourers, as the needle-like hairs on the leaf sheaths break off in the skin and can cause painful infections.



Michael Hickman
Landscape Design and Rehabilitation Specialist

www.ecoman.co.za
michael@ecoman.co.za

20.03.16



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Wednesday 16 March 2016

Vasey Grass Paspalum urvillei


Vasey grass Paspalum urvillei is a highly invasive grass which is a native of Argentina and Uruguay which is mostly found growing in damp and disturbed localities in our area.


 A monospecific stand of Paspalum urvillei

Paspalum urvillei is a large dominant grass which produces vast amounts of viable seed that displaces other grasses to form large monospecific stands largely by means of allelopathy and direct competition for resources such as sunlight, water and nutrients.


This photo gives one an idea of the average size of Paspalum urvillei

Allelopathy refers to the beneficial or harmful effects of one plant on another plant, due to the release of biochemicals, known as allelochemicals, from plant parts by leaching, root exudation, volatilization, residue decomposition, and other processes.


This photo give a clearly shows that Paspalum urvillei 
completely displaces all other species

What alarms me most about this invasive alien grass and why I see it as a huge threat in areas that are being rehabilitated is that it spreads very rapidly and colonizing vast areas and that there are no selective herbicides available that can be used to selectively eradicate it as in the case of broad leafed and other non-grassy weeds. The only options to remove this invasive grass are to dig it out or the use of non-selective herbicides such as Glyphosate which would destroy all other vegetation in the areas being dealt with therefore the sooner stands of this invasive grass are located and are eradicated the better before their seed bank increases and spreads.

Michael Hickman
Landscape Design and Rehabilitation Specialist

www.ecoman.co.za
michael@ecoman.co.za

16.03.16


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Monday 25 January 2016

The important role of the humble Dung Beetle in natural ecosystems



Dung beetles play a very important role in the health ant the fertility of natural grassland
Ancient Egyptians thought very highly of the dung beetle, believing that the dung beetle kept the Earth revolving like a giant ball of dung, linking the insect to Khepri, the Egyptian god of the rising sun.
Dung beetles belong to the family Scarabaeoidea; with most of the species being placed in the subfamilies Scarabaeinae and Aphodiinae (scarab beetles). Most species of Scarabaeinae feed exclusively on feces and are known as true dung beetles. There are dung-feeding beetles which belong to other families, such as the Geotrupidae (the earth-boring dung beetle). The subfamily Scarabaeinae alone has more than 5,000 species.

The dung beetles known as rollers, roll dung into round balls, which are used as a food source for their larvae to develop on are rolled and buried in brooding chambers that are dug into the ground. Others, known as tunnelers, bury the dung wherever they find it. A third group, the dwellers, neither roll nor burrow, they simply live in manure.

Spider Dung Beetle Sisyphus specie with dung ball
Dung beetles live in many habitats, including desert, farmland, forest, and grasslands. They do not prefer extremely cold or dry weather. They are found on all continents except Antarctica. They eat the dung of herbivores and omnivores, and prefer that produced by the former. Many of them also feed on mushrooms and decaying leaves and fruits. Those that eat dung do not need to eat or drink anything else, because the dung provides all the necessary nutrients. Most dung beetles search for dung using their sensitive sense of smell. Some smaller species simply attach themselves to the dung-providers to wait for the dung. After capturing the dung, a dung beetle rolls it, following a straight line despite all obstacles. Sometimes, dung beetles try to steal the dung ball from another beetle, so the dung beetles have to move rapidly away from a dung pile once they have rolled their ball to prevent it from being stolen. Dung beetles can roll up to 10 times their weight.
Male Onthophagus taurus beetles can pull 1,141 times their own body weight: the equivalent of an average person pulling six double-decker buses full of people. No wonder the dung beetle is known as one of the strongest animals for its size.

Spider Dung Beetle Sisyphus specie showing very long  hind legs
In 2003, researchers found one species of dung beetle the African Scarabaeus zambesianus navigates by using polarization patterns in moonlight. The discovery is the first proof any animal can use polarized moonlight for orientation. In 2013, a study was published revealing that dung beetles can navigate when only the Milky Way or clusters of bright stars are visible the only insect known to orient itself by the galaxy.

The "rollers" roll and bury a dung ball either for food storage or for making a brooding ball. In the latter case, two beetles, one male and one female, stay around the dung ball during the rolling process. Usually it is the male that rolls the ball, while the female hitch-hikes or simply follows behind. In some cases, the male and the female roll together. When a spot with soft soil is found, they stop and bury the ball, then mate underground. After the mating, both or one of them prepares the brooding ball. When the ball is finished, the female lays eggs inside it. Some species do not leave after this stage, but remain to safeguard their offspring. The larvae live in brood balls made with dung prepared by their parents. During the larval stage, the beetle feeds on the dung surrounding it. The dung beetle goes through a complete metamorphosis.

Dung beetles play a highly important role in the environment by taking animal dung that could spread various diseases amongst grazing animals and burry it in the root zone where it can be useful to the veld grasses, herbs, bacteria and fungi not leaving out the fertility and general health and structure of the soil. By burying and consuming dung, dung beetles improve nutrient recycling and soil structure simultaneously protecting domestic livestock, such as cattle goats and sheep as well as indigenous game from disease by removing the dung which, if left, could provide habitat for pests and diseases.
Most dung beetles specialize on the dung of particular animals, or types of animals, and will not touch the dung of other species.
 
Spider Dung Beetle Sisyphus specie sitting on top of dung ball
Sisyphus species - spider dung beetles
Small to medium beetles 3-12 mm black dark grey or brown hind legs very long move very energetically

Adults congregate to feed on fresh dung in particular the dung of small animals. They also feed on the dung of tortoises, birds, toads and large carnivores. The Sisyphus species form dung balls which they roll away to be buried approximately 50 mm below the surface. A single egg is laid in each ball. Sisyphus species are particularly active on hot humid days following rain. Like magic dung that has been dropped on the ground disappears due to the efforts of these highly energetic little creatures. In my case they are particularly attracted to the dung of my sheep in preference to goat dung.



Video
Spider Dung Beetles Sisyphus specie rolling a dung ball 


Michael Hickman
Landscape Design and Rehabilitation Specialist

www.ecoman.co.za
michael@ecoman.co.za

25.01.16


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Tuesday 19 January 2016

Yellow Justicia

Justicia flava

Justicia flava is known as impela in Zulu

Justicia flava
Justicia flava is an erect or trailing, usually perennial herb growing up to 120cm tall which belongs to the family, Acanthaceae. The stem often becomes woody at the base
Justicia flava is a common species found in a number of different habitats especially in disturbed habitats, growing on a wide range of soil types, in full sun or semi-shady areas at elevations from sea-level to 2,300 metres, some forms of the plant can tolerate moderate frost. It has a widespread distribution from West Africa through Central extending into Southern Africa, also occurs on the Arabian Peninsula. Justicia flava is extremely drought resistant, in very dry regions the plant can grow as an annual with smaller flowers.
Justicia flava is pollinated by insects in particular honey bees it also attracts various species of butterflies in particular small blues of the family Lycaenidae.

Cultural uses

The plant is harvested from the wild for local use as a food and medicine. In some areas Justicia flava is not removed when found growing as a weed in cultivated fields, but is allowed to grow on in order to harvest its leaves for use as a vegetable which is cooked as a spinach of used in soups and stews. In some regions the leaves are burnt to ash to produce a vegetable salt. Although it is reported that Justicia flava makes good forage for domestic animals I have observed that it is not eaten by my sheep and goats.
Justicia is used traditionally to treat coughs in South Africa. The roots are traditionally rolled into beads which remain fragrant for years.

Growing Justicia flava

Justicia flava is best grown from seed although it grows easily from cuttings
The seed capsules of Justicia flava burst open when ripe, to prevent the seeds from being lost, they must be collected as soon as the seed capsules turn brown. The seeds can be planted into trays or pots but by far the easiest is to plant the seed which germinates readily directly in situ.
Justicia flava grows best in a sunny position, but also tolerates partial shade.

Environmental value and use in the garden

Bees visiting Justicia flava
Justicia flava makes a wonderful ornamental groundcover for use in sunny spots where it can be used as a ground cover to protect and bind the soil for instance in coastal dunes and sandy river banks. It is a very valuable source of both nectar and pollen for honey bees in particular because it flowers year round under favourable conditions. In my own garden Justicia flava attracts very large numbers of insects year round at times of the year being the main source of food for them.

Warning

Justicia flava reproduces readily from seed which is most useful if it is being used for the stabilization of sandy soil but it can become a “weed” in the more formal garden. In my own garden I periodically remove the old plants to keep them under control.

Michael Hickman
Landscape Design and Rehabilitation Specialist

www.ecoman.co.za
michael@ecoman.co.za

19.01.16

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Saturday 16 January 2016

Berkheya insignis


Introducing a magnificent grassland herb from South East Africa that is practically unknown to the nursery and horticultural industry that deserves a place in every garden with a suitable climate.


Berkheya insignis is a perennial grassland herb found growing mostly on rocky slopes which grows to 400-600 mm in height belonging to the family Asteraceae, the Sunflower family.

The flowers which are a bright yellow are large 80 mm and up to over 100mm in cultivation

Berkheya insignis flower



Berkheya insignis is hardy, drought resistant and easy to grow, growing well in heavy clay soils provided they are well drained.

Berkheya insignis can be propagated from division, cuttings and seed

Berkheya insignis flower with beetle

Berkheya insignis attracts insects especially small colourful beetles



Michael Hickman
Landscape Design and Rehabilitation Specialist

www.ecoman.co.za
michael@ecoman.co.za

16.01.16

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Monday 10 August 2015

Cape honeysuckle - Tecoma capensis

Unit fairly recently this magnificent very well known shrub was known as Tecomaria capensis

Tecoma capensis this is the colour of the specimens that grow locally in Durban this one having been grown from seed obtained at Burman Bush

Tecoma capensis belongs to the family, Bignoniaceae as do many other very showy shrubs and trees such the well known , Port St Johns creeper  Podranea ricasoliana which is well known and grown in other countries yet is seldom seen or grown here in South Africa. Although a had a very large specimen growing over the roof of my granny flat at my previous house in Durban I have not yet obtained one for my property here in Mount Moreland. The photo below was taken by me in Auckland New Zealand.

Port St Johns creeper  Podranea ricasoliana

The sausage tree Kigelia africana , Rhigozum obovatum, Rhigozum zambesiacum, as well as the foreign Jacaranda are other showy well known members of the family, Bignoniaceae.

Tecoma capensis occurs naturally in thicket and is widely distributed throughout the Northern Province, Mpumalanga, Swaziland, KwaZulu-Natal, Cape coast, Swaziland and southern Mozambique.
In Mount Moreland we have natural populations growing at the south end of the King Shaka Airport and on the cliffs down by the Umdloti River.

Tecoma capensis is well known and cultivated here in South Africa it is also well known and is cultivated in many other areas around the world in particular California in the USA where many colour forms have been developed.  While living in Auckland, New Zealand I found that Tecoma capensis is a very popular hedging plant in most of the older residential areas of the city.

As a child my parents had a Tecoma capensis hedge and I loved to pick the flowers early in the morning before the birds and honey bees got to them to sip the nectar from them.

Flowering time for this shrub is very erratic and often it flowers all year round. Flowers are tubular and bird pollinated, attracting nectar-feeding birds, especially sunbirds as well as honey bees.
Tecoma capensis is an ornamental garden plant commonly used for screening and decorative purposes. It can also be trimmed to form a hedge. It is often planted specifically to attract birds.

I have seen this very dark flowering form growing naturally next to the parks board landing strip at St Lucia

Propagating Tecoma capensis
Tecoma capensis is easy to propagate from hard wood cuttings that in sandy soils can simply be pushed into the ground and watered. They can also be grown from tip cuttings in a mist propagation unit, by removing rooted suckers during the active growth phase, and from seed.

Growing Tecoma capensis 
Cape honeysuckle is an easy to grown and fast growing, scrambling shrub which is evergreen but will loose its leaves if it gets too dry or if the temperatures fall below freezing.  Tecoma capensis produces masses of orange to deep red flowers, there is also a yellow variety which unfortunately does not attract birds to the flowers.
Tecoma capensis will grow in just about any soil. When being planted it will grow best if a good sized hole is dug and is backfilled with a mixture of one third compost mixed with the soil that came out of the hole and a little balanced fertilizer. Please do not forget to water the plants as soon after they have been planted as possible to settle them in, thereafter they will need sufficient water to keep them moist until established. Once well established Tecoma capensis does not need watering as they are extremely drought resistant. In areas that receive frost young plants and larger established plants that have newly been planted out need to protected for at least the first winter.
To keep this shrub clean and tidy and to ensure heavy flowering, it must be pruned back in late winter to promote new growth and flowers.  Mulching with plenty organic compost and the application of a balanced fertilizer after pruning will enhance the growth and flowering.

Tecoma capensis is a must for every garden that has been designed to attract wildlife in particular the garden that has been designed to attract sunbirds because it provides vast amounts of nectar at the times of year when there are far less or no other suitable flowering plants for them to feed on.

Ecological value
Nature conservation starts AT YOUR OWN FRONT DOOR so anyone who is serious about nature conservation and improving the natural environment for as large a variety of creatures as possible simply has to plant a number of these highly productive plants in their own garden.

If you do not have Tecoma capensis growing in your garden and are a doer and not just a talker you will plan today to buy and plant some of these magnificent local South African plants in your garden.

Mature plants can be bought from any nursery that has a good variety of plants for sale.

Michael Hickman
Landscape Design and Rehabilitation Specialist

www.ecoman.co.za
michael@ecoman.co.za

10.08.15

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Saturday 8 August 2015

South African Bees


Most South Africans are totally unaware that there are over 1 000 known species of bees in Southern Africa

Carpenter bee Xylocopa caffra

I have had an interest in honey bees since a was a young child and have kept hives since I was a teenager. Although I was aware that there were other bee species from an early age I knew little about them until many years later. My interest in wild bees was awaked in 1988 while visiting the Garten der Schmetterlinge Friedrichsruh http://www.garten-der-schmetterlinge.de/schmettmain.html , Butterfly Garden Friedrichsruh the ancestral home of Otto von Bismarck the first Imperial Chancellor (Reichskanzler) of the German Empire which is situated a few kilometers east of Hamburg.

Giant carpenter bee xylocopa flavorufa

A year or two later I was given the booklet Wildbienen –Schutz in Dorf und Stadt Wild bees - Protection in Town and City which greatly increased my interest in wild bees prompting me to implement many of the suggestions in the booklet in my own garden in Durban and to closely observe our own local wild bees at every opportunity, an interest that has remained to this very day.

Wild bees - Protection in Town and City

Bees
Bees which are related to wasps and ants belong to the Hymenoptera order of insects, characterised by their restricted waists.
Bees are the most important group of pollinators, almost all bees are pollinators, but only a few species make honey.
Pollination is often an intricate interaction between the plant and the pollinator both pollinator and plant biodiversity together maintain healthy ecosystems.

Wild bees
South Africa has many unique wild bee species belonging to the following families;

Colletidae - Membrane bees are often referred to collectively as plasterer bees or polyester bees, due to the method of smoothing the walls of their nest cells with secretions applied with their mouthparts; these secretions dry into a cellophane-like lining.
HalictidaeThey are commonly referred to as "sweat bees" (especially the smaller species), as they are often attracted to perspiration, which are usually dark-colored and often metallic in appearance
Melittidae - They are typically small to moderate-sized bees, several species specialize on floral oils as larval food rather than pollen,
Megachilidae - are most commonly known as mason bees and leafcutter bees, reflecting the materials from which they build their nest cells.  Megachilid bees are among the world's most efficient pollinators because of their energetic swimming-like motion in the reproductive structures of flowers, which moves pollen, as needed for pollination.
Anthophoridae  - Carpenter bees which as their name indicates nest in tunnels bored into wood they are solitary bees.
Apidae- Honey bees represented by Apis mellifera and Mopane bees Meliponula species

African Honey Bee Apis mellifera scutellata

Wild bees are more efficient pollinators that honey bees
A recent global study investigated the role and contribution of wild pollinators and managed honeybees as a pollination service to a range of annual and perennial fruit, seed, nut, and stimulant crops across 41 sites worldwide. This study indicated that crop fields with high numbers of both honeybees and wild pollinators resulted in sufficient pollen deposition. In contrast, it was shown that wild insect visitation alone significantly increased fruit set, by twice as much as honeybees did, suggesting wild pollinators provide more effective crop pollination. Moreover, fruit set was shown to increase consistently with visitation from wild pollinators and increased with visitation by a diverse assemblage of pollinators independent of honeybee visitation. The additive interaction between non-Apis pollinators and honeybees has been shown to increase fruit set. Recommendations for optimal pollination therefore sometimes call for the integration of wild pollinators with managed honeybees. http://www.sajs.co.za/sites/default/files/publications/pdf/Melin_Review%20Article.pdf

Honey Bees
Twenty-eight subspecies of Honey Bees Apis mellifera (the Western honeybee) occur across Asia, Europe and Africa, but only two are found in South Africa, the African honey bee Apis mellifera scutellata and the Cape honey bee Apis mellifera capensis. The oldest known honeybee specimen dates from 100 million years ago. South Africa also has a unique problem in that the Cape honeybee (Apis mellifera capensis) can become a social parasite if introduced in the other subspecies’ (Apis mellifera scutellata) range. To remedy this, a dividing line has been drawn to separate the area in which Apis mellifera scutellata and Apis mellifera capensis can be used for beekeeping activities and no bees may be transported across the demarcation line.

African Honey Bee Apis mellifera scutellata

Honey bee pests and diseases
Much has been written about honeybee colonies around the world experiencing problems with the varroa mite pest (Varroa destructor) and diseases like, Colony Collapse Disorder (CCD) and American foulbrood (Paenibacillus larvae subsp. larvae) as a result of human interferences in regards to selective breeding, introducing foreign species into local populations and many other factors. In most cases the decline in honey bee populations can be counteracted by environmentally sound farming practices that protect natural vegetation alongside agricultural lands to allow populations of wild bees to thrive which will do the pollinating of crops that had been left entirely to unnatural practices such as transporting honey bee colonies into the orchards and fields during the flowering period to do the pollinating in the absence of large enough populations of wild bees.

African Honey Bees are not being affected to any where near that same degree as the European Honey Bee which is kept in most other parts of the world because they are more robust and resilient to pests and disease than the European Honey Bee. This natural immunity has left the African Honey Bees mostly unaffected by the global Colony Collapse Disorder (CCD) reported extensively in Europe and America as well as American Foulbrood Disease (AFB) is caused by a bacterium known as Paenibascillus larvae, so named due to the fact that it infects honeybee larvae

Attracting bees into your garden
Many of the more specialist wild bees are only attracted to our local plants therefore the bigger the variety of local grasses, ground cover plants, shrubs and trees that one has in the garden the larger the number of bee species that one will attract into your garden. The more natural the plants are arranged in the garden the more your garden will attract bees. Occasionally allow portions of your lawn to flower this will attract the most amazing number of bees including honey bees which will come to collect the pollen. 

My garden with its very large number of plants species in particular a large number of grass species attracts the most amazing variety and number of bees species. 

A plant that attracts an extraordinarily large numbers of bee species is Lilly Grass or Weeping Anthericum. This plant attracts more bee species from large carpenter bees to the very smallest bees than any other plant that I know. It is always interesting to watch these plants when they are being visited by the large bee species in particular the Carpenter bee Xylocopa caffra, because as the bee lands on the flower its weight causes the flower to drop down and as soon as it leaves to attend to the next flower it pops up again setting the whole plant in motion.


Click on the photo below to go to my blog article


The Star flower Hypoxis hemerocallidea is a charming little grass land forb that also does its fair share to bring plenty of bee species into the garden.

Click on the photo below to go to my blog article



Delospermun linearum, these little plants that I grew from a small cutting collected at Cato Ridge which I growing en mass in trays on my carport roof as well as growing in my grassland gardens is like a magnet to a very big variety of bees


Delospermun linearum

Nesting opportunities
Many bee species can be easily attracted to breed in holes of between 3 to 10 mm drilled into pieces of hard wood which are hung up in a warm dry location.



If anyone is interested in more information on attracting bees into the garden or making breeding stations for bees please contact me.

Michael Hickman
Landscape Design and Rehabilitation Specialist

www.ecoman.co.za
michael@ecoman.co.za

08.08.15

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