April 2019

APRIL 2019

The end of April ushers in our short Autumn which traditionally means that the rains will come to an end for the season. The last four years have seen suitable annual rainfall figures but the rains have fallen at the wrong time with it starting in mid-summer and raining into the winter period. This is sufficient for the water table but is unsuitable for vegetative growth as a large chunk of the growing season has been dry. This season we have had 788mm which is substantially less than our mean average of around 950mm but we have had rain fall every month of spring and summer which is during prime growing time. This, together with the large fire of August, has promoted lush growth this season. It sure is still warm enough for lots of life to be thriving and reaching their quotas in time for winter. Here are some of the goodies that have been spotted this month:

The Common Morning Glory, Ipomoea purpurea.  Originating in the tropical and subtropical areas of the Americas it has spread around the entire planet in warmer areas for it's ornamental properties. First recorded in the Durban area in 1830, this and the following three photos illustrate four different colour forms I encountered this month in the small area between Finsbury House and K9.

In tropical and sub-tropical climes it establishes itself as a perennial and can become a serious pest in gardens and cultivated fields. But in areas where frost occurs, like here, the plant establishes itself as an annual and cannot grow very big so it does not become a pest. 

The most famous of all the representatives of the Morning Glory genus is the Ipomoea batatas, the Sweet Potato, also originating in the tropical Americas, whose flowers resemble these in size and structure but are more bland in colouration like the two indigenous species I have so far encountered here on the Estate.  

The seeds of this plant contain a powerful hallucinogen and therefore even a small number present in maize grain causes the crop to be down-graded, affecting the price of the crop.

A close up of the female in a mating pair of Crane flies from the Tipulidae family of flies. Because she emerges from her pupa already bloated with eggs, the distended abdomen of this individual indicates her sex. Since the adult only lives for a mere two weeks, the female must find a mate as soon after emerging from her pupa as possible. After mating, she lays her eggs in very dark, moist places where the larvae, called Leatherjackets, burrow into the substrate and consume living or dead vegetable matter. These Leatherjackets are serious pests to certain agricultural crops but were made known to the layman in 1935 when thousands of Leatherjackets were removed from the wicket of Lord's Cricket Ground in London resulting in bare patches that introduced an unaccustomed spin for most of the season!

Most insect larvae eat a very different food type to the adults of the same species. This reduces competition for food amongst the same species and puts different generations in different environments. Not so with this Ladybird from the Coccinellidae family of beetles. This beetle finds a large colony of Aphids (pictured) or Scale insects, both the worst enemy of the avid gardener, and deposits her eggs in amongst the colony. She then proceeds to stuff herself with the sap-sucking insects (pictured) and when her larvae hatch from their eggs, they also voraciously consume the aphids. Truly a gardener's best friend! But they were released as a biological control organism in the US as early as 1916 and they are now the pest, out-competing the local insects and establishing themselves as the most widespread Ladybird in the US today.

Although most trees are bearing fruit by autumn time, these beautifully inscripted pea-flowers adorn the Grassland Hook-leaf Pea, Otholobium wilmsii, at the moment. This attractive little tree is not common but can be found in forest fringes at high altitudes.

Considering the lush growing season and the fact that there was still plenty moisture in the soil, we decided to burn our first Patch Mosaic burn block in the south west of the Estate. With a patch mosaic burning policy we divide the Estate into much smaller blocks than was traditional. We then burn alternating blocks in successive years during the rainy season when lightning is common, simulating natural lightning fires. Because the fire is cool, resulting from moisture and green growth, the fire will not burn areas that do not have sufficient moribund (dead vegetable material). This will reduce the risks that fires pose and reduce the labour required for normal burning because the fire will not burn easily into more recently burned adjacent blocks, containing it safely. 

With only two small blocks remaining on the Estate that require a conventional fire, we will begin our patch mosaic project next summer. This will reduce run-off into the weirs; create evenly spread grazing for the animals; reduce the labour required for fire work; put an end to the huge, uncontrollable fires experienced in the past; and benefit the grassland ecosystems immensely. In the picture above, you can see a storm gathering over the fire. Needless to say, the fire was extinguished before it finished burning the block.

The Golden-spotted Sylph, Metisella metis, is a common Skipper found on the Estate throughout the year. The golden spots adorn the butterfly like jewellery, as in the mythical Metis, the original spouse of Zeus. The larvae feed on various grass species. 

In my February blog, I posted a picture and a little information of a Spittle Bug from the Cercopidae family of bugs. That was the nymph feeding off the copious amounts of plant sap, filtering it to extract the nutrients and excreting the waste as foam spittle to protect it from the elements and its enemies. This is the adult, called a Froghopper because it is squat like a frog, and it can jump like a frog although it springs more like a flea. 

We decided we wanted to offer the young 'uns something more exciting to keep them occupied this Easter break. So I compiled a workbook outlining a basic mountain survival course. We had bookings for 11 kids to attend but by the time Easter weekend arrived, there were only two left to enjoy (or not!) it. They were Joel (foreground), a visitor at Morrin Pools and his school buddy, Christian. The course covers mind control; dangers one may encounter in these mountains and how to avoid them; and orientation in the day and night. One of the biggest dangers one could face here is lightning strike and soon after we set off on the adventure, a lightning storm hit us from the south which was not in the forecast for the day! we had to descend into a gorge quickly and after waiting out the storm, we ascended again (you can see the haze of the storm heading north on the left of the picture). Talk about a practical course!

This is a panorama shot from the tippy top of the summit of Mount Anderson, facing west. It was full moon, so we wanted to see the moon rise while the sun set but you can see the clouds rolling up over the watershed on the left from the Sabie Valley, so the moon-rise was not so visible but we did have a spectacular sunset. note the guys are wrapped in space blankets because at this stage, the wind chill was getting to our bones...

The following morning, as the sun rises and the shadow reaches our camp, Christian walks through the soaked grass to join us sunning ourselves after a cold, wet night under the stars. The course was not very structured because it was the first time but it will improve next time. Get the kids ready! I will do a course for your kids anytime if you give me notice. 

If you are exploring the dark, afrotemperate forests on the Estate and you see a flash of colour pass by low to the ground, it may be a Dry-leaf Commodore butterfly, Precis tugela tugela. If you want a better look at it, follow it with your eyes and carefully mark the spot where it lands....

Because if you don't mark it carefully, you may never find the butterfly although it is right under your nose! when it lands it closes its wings and the undersides look just like a dead leaf, even differing from individual to individual! I had this one in my sights and I was still unsure if I had the right thing even when I was less than a meter away.

The Banded Garden Spider, Argiope sp., is a large brightly coloured web-living spider that is found in grasslands and areas with low vegetation all over the world.The spider spins a large but flimsy orb web about a meter above the ground and then waits for prey upside-down in its centre. Usually, close to this central area on the web, the observer will notice a zig-zag pattern of silk called a stabilimentum. There are many theories to the function of this zig-zag of silk, from reflecting UV light to attract insects, to making the web visible to larger mammals so they don't walk through it. But as its name suggests, it may just be there to stabilise the particularly flimsy web.

This beautiful Leopard was spotted, by the Moores from Rock Solid, on the other side of the Klipdrif stream in the bottleneck of South Valley at the end of April. After explaining its location to me, I rushed over there and it was still lying in the same place described to me but it was dark by that time so I didn't get as good a look. Nick said it was a large male leopard and, looking at the photo, I agreed, thinking he was the new big guy on the block. But after comparing the spot pattern on the bib and elsewhere, it appears to be the big female the Beaumonts from Cochybundu spotted and photographed nearby some time back. It looks like she has a whole Reedbuck in her tummy... 

As we enter the month of May, so do we change seasons and already one can feel the change in temperature and notice the shortening of the days. The water levels are still nice and high and the fishing is great so bring yourselves to the mountains as soon as you can.

To all who knew Doctor Mack Rogan, our sincerest condolences. Dear Mack, I'm going to miss you terribly. RIP.