Magnolia scales, Neolecanium cornuparvum, are amongst the largest scale insects to infest shade trees, with some individuals reaching ½” in length. As the common name suggests, this scale is a frequent pest of magnolia species, including star, saucer, and the cucumber tree.

A conspicuous pest in mid to late summer, they cause damage to trees by weakening and girdling branches while producing a sticky ‘honeydew’ on leaves and targets below.

Susceptible Hosts
* Star Magnolia (Magnolia stellata),
* Saucer Magnolia (Magnolia soulangeana),
* Cucumbertree Magnolia (Magnolia acuminata)
* Lily Magnolia (Magnolia liliiflora).

It has also been reported that magnolia scale feeds on
* Daphne spp.
* Virginia Creeper (Parthenocissus  quinquefolia),
* Tuliptree (Liriodendron tulipifera).

Pest
Neolecanium cornuparvum

Symptoms
* Sticky honeydew on leaves and targets underneath the infested tree.
* Dwarfed or stunted growth on infested twigs.
* Branch decline on severely infested twigs.

Signs
* Newly hatched crawlers are a medium brown color, getting darker after feeding commences.
* Presence of large, oval shaped dark brown insects on twigs and branches, often in high population numbers

Life Cycle
* One generation per year.

* Nymphs mature in late July through early August. Males emerge about the same time as small fly-like insects which mate with females and then die. Females later give birth to living young called crawlers in late August or early September. These nymphs or crawlers wander about for a short period of time prior to settling down on the young twigs where they overwinter.  

Distinguish from Look-alikes
Magnolia scale can appear similar to other scale insect pests but the large size and host specificity are good indicators

Xytect should be applied in late summer/early fall of the previous year to kill next year's crawlers.  Spring soil applications of Xytect will also provide acceptable levels of control.  
Transtect can be applied to the soil in late spring to kill current year crawlers.    

Apply PureSpray Summer sprays and Bisect to crawlers at 2155-2800 GDD.

Re-treatments:
Annual treatments

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