Knysna-Plett Herald

Beet­le-bus­ter dis­pu­te

- Lee Jay

Just days af­ter it was an­noun­ced that a "so­lu­ti­on" has fi­nal­ly been found to the tree-kil­ling beet­le pro­blem in the coun­try, a group of s­cien­tis­ts slam­med on the bre­aks.

Pro­fes­sor Wil­helm de Beer who le­ads the po­lyp­ha­gous s­hot-ho­le bo­rer (PSHB) net­work of 17 a­ca­de­mi­cs at the U­ni­ver­si­ty of P­re­to­ria, says t­hey ha­ve not star­ted tes­ts on the much-de­bated la­test pro­duct by Pan A­fri­can Farms (PAF) in Pa­rys in the Free S­ta­te.

"I am not saying the pro­duct does not work," con­tends De Beer. "W­hat I am saying … is that the e­vi­den­ce pro­vi­ded is not at all suf­fi­cient to back claims a­bout the pro­duct. The de­sign of the ex­pe­ri­ment is not good e­nough. The ex­pe­ri­ments do­ne in a lab and field are in­suf­fi­cient and claims or con­clu­si­ons are mis­le­a­ding."

'How can he jud­ge?'

But PAF CEO Pie­ter Mey­er re­sponds, "I ga­ve him (De Beer) sam­ples and I don't know if t­hey did tes­ts, but w­he­re is his e­vi­den­ce? How can he jud­ge? He has not e­ven seen all the re­se­arch."

De Beer al­so que­s­ti­ons the re­gis­tra­ti­on pro­cess of the pro­duct. "I am ac­tu­al­ly a­ma­zed that the pro­duct has been ap­pro­ved, but w­hat pe­op­le must al­so re­a­li­se is that it on­ly got tem­po­ra­ry ap­pro­val for ex­pe­ri­men­ta­ti­on. But now so­meo­ne mig­ht be mis­le­a­ding pe­op­le big ti­me and ma­ke a lot of mo­ney."

The­re is in­deed "a lot of in­te­rest", ac­cor­ding to Mey­er, who says t­hey ha­ve ma­ny or­ders for the pro­duct and feed­back has been po­si­ti­ve. "We are o­pe­ra­ting within the con­fi­nes of the law. W­hen it co­mes to Prof de Beer, I re­al­ly st­rug­gle to con­t­rol my­self. But you don't fig­ht fi­re with fi­re. I am ir­ri­ta­ted. The so­lu­ti­on is de­fi­ni­te­ly not to start chop­ping off first a hund­red trees, then a mil­li­on and then 10-mil­li­on. If we can just sa­ve half it's worth it," says Mey­er.

'Don't pa­nic'

Sil­vi­cul­tu­re spe­ci­a­list Dr Jaap S­teen­kamp who ma­na­ges PSHB tre­at­ment in Ge­or­ge and sur­rounds, be­lie­ves the most im­por­tant thing w­hen you find e­vi­den­ce of the beet­le is to not pa­nic, but ap­pro­ach the pro­blem in a lo­gi­cal way.

He says e­ver­y­bo­dy is look­ing for a so­lu­ti­on and the­re are ma­ny tre­at­ments, in­clu­ding sound fre­quen­cy to re­pel the beet­les, that mig­ht be wor­king.

"We ha­ve been very success­ful and ha­ve sa­ved ma­ny trees… We use a va­ri­e­ty of pro­ducts to ma­ke a cock­tail…" says S­teen­kamp.

"We on­ly star­ted u­sing the PAF pro­duct a­gain on 1 Au­gust, sin­ce the pre­fer­red met­hod of ap­pli­ca­ti­on is sy­s­te­mic con­tact tre­at­ment (in­jecti­on) which can on­ly occur du­ring the gro­wing se­a­son, and it is wor­king. But the pro­duct PSHB Fun­gi­ci­dal on­ly ad­dres­ses the fun­gi (or beet­le food) and le­a­ves the beet­les un­tou­ched. In my o­pi­ni­on t­hey look for new trees long be­fo­re t­hey star­ve to de­ath," says S­teen­kamp.

He cau­ti­ons a­gainst an at­ti­tu­de of "Not in my gar­den!". "It is very im­por­tant not to go co­w­boy or cut off an in­fected tree and just throw it on the trai­ler and speed all the way to the dump," he says. This will on­ly con­tri­bu­te to the spre­ad of the beet­le, he adds.

W­hat a­bout bur­ning?

Com­bus­ti­on of moist tim­ber is slow and may con­tri­bu­te to spre­ad PSHB, says S­teen­kamp. "In­ci­ne­ra­te is dif­fe­rent but in­fected trees that are fel­led must be spray­ed with Cy­pe­methrin which is a­vai­la­ble at the lo­cal co-op."

That being said, tre­at­ment is bet­ter and che­a­per than fel­ling, S­teen­kamp be­lie­ves. He ad­vi­ses to ob­ser­ve in­fected trees lo­gi­cal­ly, mo­ni­tor them clo­se­ly and tre­at with both an ef­fecti­ve in­secti­ci­de and fun­gi­ci­de and pre­fe­ra­bly va­ri­ous met­hods of ap­pli­ca­ti­on in­clu­ding spray and in­jecti­on.

Lucki­ly the im­pact on in­di­ge­nous trees, he says, is not big ex­cept for suscep­ti­ble spe­cies li­ke y­el­low­wood. The beet­les still pre­fer in­va­si­ve hos­ts but fruit trees and es­pe­ci­al­ly a­vo­ca­do trees are very suscep­ti­ble.

Tell-ta­le signs of the bo­rer beet­le are litt­le ho­les of 1mm in di­a­me­ter, dark spots and w­hi­te ex­cre­ti­on. "It can look li­ke a shot­gun was fi­red at the tree. Trees with a rough bark are toug­her to i­den­ti­fy. In­fected and untre­a­ted trees may die within mont­hs. We ha­ve e­ven found in­fe­sta­ti­on in bon­sai," says S­teen­kamp.

Newspapers in Afrikaans

Newspapers from South Africa