Integrated pest management has gained a firm foothold in the pest management strategy of KwaZulu-Natal macadamia farmer Wally Klar. Not only is it having a positive impact on tree health – but the orchards are buzzing with life.

Author: Robyn Joubert

This article appeared in Landbouweekblad on 11 Nov.

FOR YEARS, north coast macadamia farmer Wally Klar has been tinkering with integrated pest management (IPM) to tackle problems in his orchards. This environmentally sensitive approach takes guts and nerves of steel – but it’s earning its stripes.

“I’m a conservationist at heart. We are always looking for ways to be kinder to the soil and to find a more sustainable alternative to chemicals,” says Wally, who manages Andy and Steve Dahl’s 100ha Fawsley Farm in Kearsney, KwaZulu-Natal.

Fawsley Farm has 85ha mature 15-year-old trees; and 3ha of newer one- to three-year-old trees.

“I inherited these orchards, warts and all, when I arrived in 2010. We’ve lost a number of trees over the years to problems like wind, waterlogging and phytophthora. And we are still hurting from a lack of land preparation at the time of planting. The soils are not the greatest either: they are shallow and very sandy.”

Faced with these challenges, and with yields of only 20 tons, Wally had his work cut out for him.

Quality is King

One of Wally’s biggest successes at Fawsley Farm has been in producing nuts of exceptional quality. “We are achieving a very low level of unsound kernel. For the last few years, we keep the rate at under 1% unsound kernel. Our best seasons have been 0.4% and 0.6%.  This season we are far below the factory overage of  2,7%.”

Yields have shot up from 1ton in 2010 when Wally first arrived at the farm, and now fluctuate between 210 and 250 tons.

He was top Mayo Macs top producer in SA in 2015, and was Coastal Macs top KZN producer in 2019 with 0.57% USK “It was pleasing to have a record crop and good quality.”

The entire crop goes to Coastal Macs for processing and marketing, apart from reject nuts which are sent to a confectionary producer. “The only other real value is husks which are composted and applied back into orchards. There is no other value adding – the crop is sold overseas to a dollar based market and it’s hard to beat that.”

For the last two years, beneficial insect have been released to help in the management of pests such as thrips.

“Thrips is present on the flowers but it is unclear as to whether they cause actual flower damage. The problem is that after flowering, thrips have no food so they either destroy the new leaf flush or eat at the husk. There is no real damage to kernel quality but the husk turns brown. I maintain that this opens the nut up to secondary infections like husk rot and premature nut fall.”

A great one to tinker and experiment with biological IPM, Wally is having some good results. Tree health is improving and with it, nut yields and quality.

“However, you can’t put IPM on a pedestal. There is no silver bullet. We have worked hard over the years to get where we are. We’ve put in sub-surface drainage and ridged up to reclaim and maximise the area available to us. We’ve been mulching and bringing in kraal manure, lime and gypsum, and we still rip next to the trees to try soften up compaction.”

Impact of biological products on nature

By displacing chemical inputs with biological products, there are less chemical residues on the nuts and in the soil and water systems. This has a favourable impact on the environment.

“The variety of birdlife in our orchards is unbelievable. We get everything from seedeaters to fruit eaters and insectivorous birds. Birds like shrikes and drongos are now spending all day in the orchards and contribute to stinkbug control. There are also fruit-eating birds, who must be getting their protein from caterpillars, aphids and spiders."

“At flowering, I see masses of beneficial insects contributing to pollinating: wild bees, butterflies, ladybirds and lacewings. We made a decision to not bring in hives this year because we have enough insects for pollination.”

In 2020, Wally stopped mowing the grass in the orchard interrows. “My scouts noted stinkbug in the grass so we left it to grow. By December, the grass was as high as a bakkie and looked like a dog show. But when we started cleaning the interrow in preparation for the harvest, the stinkbug numbers started increasing. That told me that the insect life is happier when left undisturbed.”

Little flowers like blackjacks are also growing in the interrows; and Wally has planted African basil in strategic points to attract bees. “When I stand in an interrow, I just see things buzzing around me. I am very happy to see all this life in the orchard. It makes me feel we are on the right track with this friendly route.”

When it comes to IPM, each farm has its own microclimate and challenges and farmers need to do their groundwork to see good results.

“You have to scout properly. Without information from the fields, you’ll be in trouble. Rob Hellig, a technical representative from RealIPM, comes to visit once a week. We spend a lot of time in the orchards looking at how we can maximize these biologicals. I don’t always understand how we get the results we do. Sometimes I am flabbergasted by the results. All I know is that it does work.”

Wally's top three rules

Wally’s top three contributors to a good mac crop are timing, scouting and spraying.

Timing is critical

I live by timing. The July riots in KwaZulu-Natal impacted transport and delayed deliveries of inputs like gypsum and fertilizer. Even though we have irrigation, nothing beats the rain. I try to time a fertilizer application a day before the rain. Timing is also critical to stinkbug control.

We live by our scouting routine.

We scout three mornings a week if the weather plays ball. In summer, my scouts are out at 3am to catch bugs when it’s dark and cool. The information we get back from the scouts informs the pest control strategy and timing thereof.

It’s difficult to time a spraying application correctly.

With nut borer, you can see the eggs on the nuts but rain or mist might prevent you from spraying. It is frustrating. We only have 200 trees a hectare – the industry norm is 312 trees – which gives us a lot of space to move and the mist blower probably gets better penetration because of it. The Dahls have invested in two cab tractors and two mist blowers so we can get in to spray quickly when we need to. The cab tractors are a real game changer because we only spray at night and we want that comfort for our drivers.