{"id":31,"date":"2022-08-19T06:42:07","date_gmt":"2022-08-19T06:42:07","guid":{"rendered":"https:\/\/blogs.oregonstate.edu\/hazelnuts\/?p=31"},"modified":"2022-08-22T17:00:29","modified_gmt":"2022-08-22T17:00:29","slug":"osu-orchard-crops-research-and-extension-program","status":"publish","type":"post","link":"https:\/\/blogs.oregonstate.edu\/hazelnuts\/osu-orchard-crops-research-and-extension-program\/","title":{"rendered":"Organic production research – Orchard Crops Research and Extension Program"},"content":{"rendered":"\n
\n
\n

Organic Hazelnut Farm Tour E-Handout, <\/strong>Aug. 19, 2022<\/p>\n\n\n\n

Nik G. Wiman (+ Team), Orchard Specialist & Associate Professor<\/p>\n\n\n\n

contact: Nik.Wiman@oregonstate.edu<\/a><\/p>\n<\/div>\n\n\n\n

\n
\"\"<\/figure>\n<\/div>\n<\/div>\n\n\n\n
  1. Organic Pest Management<\/strong>
    1. Aphids
      1. Aphid management tactics<\/li>
      2. Aphid biological control<\/li><\/ol><\/li>
      3. Filbertworm
        1. Organic sprays<\/li><\/ol><\/li>
        2. BMSB
          1. Organic sprays<\/li>
          2. Biological Control<\/li><\/ol><\/li><\/ol><\/li>
          3. Cultural Practices<\/strong>
            1. Production levels with no sucker controls compared to single trunk<\/li>
            2. Grafting to reduce suckering<\/li>
            3. Cover crops – new soil health project<\/li><\/ol><\/li><\/ol>\n\n\n\n
              <\/div>\n\n\n\n
              \n
              \n

              1.A.i. Aphid managment tactics. <\/strong>Aphids may not normally be a problem in organic hazelnuts. In an older study that took place in unsprayed hazelnut blocks, aphids were not a pest, the populations were kept at low levels by the natural enemy community. However, certain organic insecticides that are used to control pests such as filbertworm (such as spinosad) can be disruptive to the natural enemy community and can increase risk that aphids will become problematic. Aphids can impact yields (reduced fill) and impact tree health and vigor. There are two species that affect hazelnuts; filbert aphid (Myzocalis coryli<\/em>) and hazelnut aphid (Corylobium avellanae<\/em>). <\/p>\n\n\n\n

              Both species spend the winter as eggs on twigs and branches and begin hatching around budswell. As they hatch they begin feeding on the buds, before moving to the underside of the leaves. At that point, the two species begin to occupy separate niches, with the filbert aphids staying on the leaves, and the hazelnut aphids start moving on to the leaf petioles and shoots and eventually hazelnut aphid move to the husks. As soon as these overwintered aphids make oit to the adult stage, they start giving live birth to nymphs and populations increase rapidly.<\/p>\n\n\n\n

              While OSU has developed thresholds for treating aphids based on the number of aphids per leaf, we wanted to try some other tactics. Instead of waiting for aphids to increase, could we spray organic crop oils to knock back the aphid populations early in the season before the natural enemy community becomes active? We have had good success with this tactic. Oils smother aphid eggs and early nymphs. We hope to see superior spray oil be registered for hazelnuts as it will be very useful for organic growers. Meanwhile botanical oils (such as neem) can be used for organic and there are a number of these registered for use in organic hazelnuts. A big question for this research was regarding the safety of using oils on hazelnuts because they are not widely used, but we have not seen any phytotoxicity issues.<\/p>\n\n\n\n

              <\/p>\n<\/div>\n\n\n\n

              \n
              \"\"
              Initial egg hatch occurs at budswell. Photo: Heather Andrews<\/figcaption><\/figure>\n\n\n\n
              \"\"
              Hazelnut aphids are segregated along the stems whereas filbert aphid is more concentrated along the lateral and mid leaf veins.<\/figcaption><\/figure>\n\n\n\n
              \"\"
              Extreme infestation of hazelnut aphid on husks. Photo: Heather Andrews<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n
              \"\"
              Botanical oils (Rango and AzaDirect are registered for organic use and are neem products) did a good job in reducing initial aphid problems without impacting biological controls (data not shown) up to at least 14 days after treatment (DAT) when applied at budswell on ‘Jefferson’. Superior mineral oil is also effective but is not<\/span> yet registered for use in hazelnuts although it is an organically acceptable oil in other orchard crops. Results from new trials are evaluating entomopathogenic fungi and some other organic materials for aphid control coming in 2023. Thanks to Oregon Hazelnut Commission for support of this work.<\/figcaption><\/figure>\n\n\n\n
              <\/div>\n\n\n\n
              \n
              \n