Gaeumannomyces graminis var. tritici (Ggt) soil DNA inoculum levels in wheat fields were studied in New Zealand as part of work to identify wheat fields with a low risk of take-all. Ggt DNA inoculum levels have been identified overseas as peaking near the harvest date of wheat then declining. Early sowing is also reported to increase take-all infection. The changes in Ggt inoculum levels that occur during the post-harvest period in New Zealand and the implications were for the risk of severe take-all were unknown. Ggt DNA inoculum levels were monitored over the pre- and post-harvest period from February to July in 12 commercial wheat fields. For 10 second wheat fields, mean post-harvest inoculum levels peaked in March at 378 pg Ggt DNA/g soil. Mean inoculum levels then declined at each subsequent sample to the final sample in July when levels were less than one-third (103 pg Ggt DNA/g soil) of those in March. Linear regression was used to quantify the level of decline- from 1 March to 1 July predicted Ggt DNA levels declined by 78%. In two second wheat fields, post-harvest Ggt inoculum levels were also evaluated using an infectivity bioassay method. The bioassay results supported the declining Ggt inoculum levels observed using the Ggt DNA method. An implication of the results was that early sown consecutive wheat will be challenged by higher Ggt inoculum levels than late sown consecutive wheat.