Monday, 14 May 2012

Lemon Tree, Very . . . Weird


This very strange looking lemon came from a large, otherwise healthy tree with lots of normal fruit on it.

The deformity is caused by the citrus bud mite, a tiny, worm-like mite (about 0.17 mm long and 0.05 mm wide).The mite feeds on either developing leaf or flower buds. Affected leaves are disfigured and some affected flower buds can continue to develop, producing some very weird shapes in the surviving fruit. In heavy infestations, the fruit fails to develop and drops from the tree at an immature stage. Mite infestations are most common in lemon trees and navel orange trees and in coastal areas.

If the tree is otherwise healthy and distorted leaves and fruit are few, no treatment of backyard trees is necessary. If the infestation is severe, or for commercial growers, treatment can be by either sulphur spray or white oil spray. Home-growers can spray white oil when flower buds are developing or when the tree is showing a flush of new growth. Alternatively, cut off the stems bearing affected leaves and fruit and put them in the rubbish bin. The mites' life cycle is continuous throughout the year, but their numbers seem to be reduced during hot, dry weather.

Friday, 11 May 2012

Beautiful Birds and Other Garden Friends




One of my aims when developing this garden was for it to be a biodiversity haven. I chose plants to encourage beneficial insects and to provide food and habitat for birds of all kinds. Nine years on the garden is full of life: myriad insects, birds, lizards and frogs are either residents or frequent visitors. Some we see on most days, others are not uncommon, still others occasionally use the garden as a resting/feeding spot before moving on. For a few days we were visited by a dollar bird, a refugee from bushfires further north, but we have never seen it again. Birds of prey are not common, but have been seen in our trees on a number of occasions.


Frequent visitors are several types of honeyeaters and rosellas. Today, we saw both crimson and eastern rosellas eating berries on a crepe myrtle at the same time. The erica 'White Delight' is a favourite with wattle birds, eastern spinebills, blue-faced honeyeaters and New Holland honeyeaters, to name its most frequent visitors. Neither of these plants is a native, yet both are beneficial to the biodiversity of the garden. The erica is almost always in flower and is so popular with so many birds that I now have three of them planted close to the house. Grevilleas, banksias, and callistemons are also often visited by honeyeaters.




Grasses provide food for the little seed-eating wrens and finches, and the insects that are here in abundance provide food for numerous birds, including being part of the honeyeaters' diet. The biodiversity web of my garden becomes more complex and interesting as time passes and birds are an important strand of this web.





Tuesday, 8 May 2012

Crazy About Crepe Myrtles

The crepe myrtle (Lagerstroemia spp) is one of my favourite flowering trees. They are not Australian natives, but are quite hardy and will survive with little water once established. Different cultivars come in a range of sizes to suit most gardens. They flower spectacularly for months from summer through to early autumn, the autumn foliage display of many species is beautiful for weeks on end, and even in winter their bare branches (often festooned with sparkling spider webs) are usually aesthetically pleasing. As well, they produce berry-like seeds, which the rosellas around here like to eat during the colder months. The timber has been used to make furniture, but I won't be cutting mine down for that purpose. A common problem with older cultivars is powdery mildew, but mildew-resistant cultivars have been around for some time. I recommend a crepe myrtle to anyone wanting an attractive flowering tree.

Sunday, 6 May 2012

Resilience After Bushfire

Yesterday we visited some people in Kinglake who had been through the Black Saturday bushfires. Jane and Sean lost their house, cars, possessions and garden, have been living in a well-fitted-out barn for about three years and are now just beginning to build a new house. Across the road and slightly lower on the hill, Julie and John's house survived unscathed, but embers did blow under the door and have to be extinguished. The fire by and large leapt over their garden, though spot fires had to be quenched. The intense heat caused most of their plants to drop their leaves, but they did not actually burn and most soon recovered.

Jane and Sean and their teenage granddaughter took refuge with Julie and John after narrowly escaping the fireball that engulfed their house. Both couples camped out on the unburnt lawn in front of John and Julie's house for the next few nights, feeling unsafe to be indoors. They watched the surrounding bushland burning and listened to trees falling and gas bottles exploding.

The aim of our visit was to research a book about garden recovery. Though Jane and Sean lost most of their garden (a few large trees were damaged, but did eventually recover), some plants did come back. Tree-sized camellias were lost, but a few have recovered. One is just now, after over three years, regrowing from the roots. Some plants that recovered are doing better than they did previously, and some (such as lavenders) that would not grow before are now thriving. Maybe this is as a result of the increased light, or maybe because of the ash from the fire decreasing the acidity of the soil.



Huge mountain ash trees died in the blaze, but numerous young trees, far too many and too close together, have regrown from seeds.


Jane told me that after a natural disaster 30 to 40 percent of the people affected leave the area. After seeing the remains and hearing the stories, I'm impressed once again with the resilience of the human spirit that enables so many to make the decision to stay and with the resilience of the natural systems that are driven to recover, albeit with different species mixes from those in place before the fire. I'm very grateful to Jane, Sean, Julia and John for sharing their stories.

Saturday, 5 May 2012

Autumn Colour

Today I decided to share some of the colours of autumn I have been enjoying on my walks around town in recent weeks. If your garden is looking a little dull at this time of year, take note of flowers and colorful foliage trees in nearby gardens and streets. This is a great time to be establishing new plants so your garden's autumn colours will be admired in future years. 

























Thursday, 3 May 2012

Strawberry Jam

Last winter I fertilised the strawberry plants with a slurry made from worm castings. They rewarded me with the best crop we've had for years. By midsummer I was sick of picking them, even sick of eating them. Then we had quite a good autumn crop as well. I still can't believe I actually said, 'Oh no, not more strawberries'.

I preserved the berries we didn't eat by freezing them in a single layer on a tray, then, when they were frozen, transferring them to bags for long-term storage. A whole shelf of the freezer has been taken up with frozen berries, not just strawberries; the youngberries produced prolifically as well, and also made their way into the freezer. The intention was to use the frozen berries to make jam on a cold day.



Today was the day. The house smells like a jam factory and I now have 11 jars of strawberry jam. The youngberries are still waiting. It will be a while before I get to them because I've run out of jars. Red and green tomato chutney made in the summer and today's jam have used all my saved jars.



Excess plums and apricots can be similarly frozen at the peak of the harvest (halve them first) and brought out in the colder weather to turn into jam. A hint for anyone who does make strawberry jam: add the juice of a lemon to the fruit mixture to help it set as strawberries do not contain the pectin required for the jam to jell.    

Tuesday, 1 May 2012

Interesting Things About Lichen

With muscles stiff from last night's pilates class and a brisk breeze in my face, the body was feeling its age as my morning walk took me along a little-used road at the edge of town. A person could collapse on this road and no one would come along for hours, was the gloomy thought that flashed through my mind. As I thought this, I looked down at the road surface and noticed it was covered in lichen, then remembered a book I'd read years ago that included some amazing information about lichen.

I suppose nearly everyone knows that lichen is a symbiotic relationship between fungi and algae. Nestled among the mats of fungal hairs (hyphae) are minute single-celled algae. Lichens are exremely drought hardy and can survive the harshest summers on rocks and roofs exposed to the full sun. They might look dry and dead, but it only takes some rain to reinvigorate them.

Surprisingly then, they are very intolerant of air pollutants. So much so that they are used as biological monitors. Different types of lichen react to different types of pollutants. Some are useful monitors of sulphur dioxide, a common industrial pollutant, as they are unable to survive when it is present. The number of lichens increases with distance from industrial areas. In areas or towns where the air is unpolluted, lichens thrive. I've often noticed the lichens growing on old tile roofs around the country town I live in. Sometimes there will be a streak of clean roof standing out from the lichen-encrusted tiles, where the smoke from a chimney blows across it and I wonder what is burnt in that fireplace.


Other lichen species are sensitive to acid rain, airborne heavy metals and radioactivity. These latter can be used as a record of accidents at nuclear power plants or of atmospheric testing of nuclear weapons.

As well as their use as biomonitors, lichens do have a more down-to-earth use. When we lived a fairly self-sufficient life on a small, rocky acreage, I once used lichen collected from the rocks to dye some hand-spun angora fleece (shorn from our own goat), which I then knitted  into a jumper for my son. The colour turned out to be a mustardy brown. The photo below shows the type of lichen used for dyeing.


Lichen is often found in conjunction with moss. Mosses are also sensitive to pollutants, and some species accumulate toxins which can be analysed to show patterns of pollution from industrial sources.



The above uses only scratch the surface. Lichens have been used as food and in medicine, perfumery and embalming, and for much else besides. Some lichens are poisonous, so please don't go putting your local species in a salad. An interesting medicinal application is that about half of all lichen species are antibiotics and some lichen extracts kill the bacteria that cause boils, scarlet fever and pneumonia. I wonder now about the possible properties of the various lichen species on the rocks in my garden.


For any readers interested in the many ways that natural systems benefit our lives, this book is absolutely fascinating: Wild Solutions by Andrew Beattie and Paul R Ehrlich, published by Melbourne University Press
2001. Perhaps your library has a copy.