[1] Second, he adopted the writings of Paul Schultze-Naumburg to landscape and technology as well as the design of biodynamic agriculture of the anthroposophy of Rudolf Steiner.
The fact that he had also acted as a contact person for the anthroposophical movement made him suspicious in the eyes of the Reich Security Main Office, which had him monitored temporarily in 1941.
He used this function to get in close contact with Nazi party leaders; He conducted intensive correspondence with Rudolf Hess, Martin Bormann, Heinrich Himmler, Walther Darré, Albert Speer, and Oswald Pohl.
So he demanded in the polemic The desertification of Germany, to create the position of general inspector for the German water industry including a research institute.
Seifert, who became an influential advisor to Todt, gathered landscape architects, plant sociologists, and conservationists around him, with whom he tried to implement his ideas.
In particular, he was instrumental in ensuring that every top construction management of the Reichsautobahn got its own "landscape attorney", who was responsible for all the relevant measures and was involved in the staking out of the motorway routes.
In addition, he perceived steppe landscapes as "un-German" and demanded that the Eastern European areas conquered by the Wehrmacht be "Germanized" by planting field hedges.
He criticized Rudolf Hess for the fact that the Nazi racial ideology was too one-sidedly “Nordic” and wanted to see an “Alpine race” included in it.
[12] Seifert succeeded in the denazification process initially as a “fellow traveler”, later (1949) to be classified as “unencumbered” because he had to accept “considerable economic and professional disadvantages” under National Socialism.
He got himself influenced by anthroposophy in the early 1940sturned away from his “racial arrogance”, which was born out of his materialistic attitude and which had buried the natural instincts for the real values of a person for more than a decade.
Phillip Auerbach, as State Commissioner for Racially, Religiously, and Politically Persecuted Persons, was appalled and initiated a retrial against Seifert, which ended in the second instance in October 1949 with the classification as "unencumbered".
Seifert stood up for the biodynamic economy with great moral courage, spoke out in favor of Jews and politically persecuted students and accepted financial and professional disadvantages in the process.
When these were finally available, it became clear that Seifert was by no means only patronized by Todt and Hess, but was in close contact with a large number of top party officials and that Himmler, Speer and Pohl had systematically advocated him.
In 1961, Seifert was one of the 16 signatories of the Green Charter of Mainau, which was initiated by Count Lennart Bernadotte and announced on site by Federal President Heinrich Lübke.
With his book Gärtnern, Ackern ohne Poison, which is still published today, he wrote a work on organic farming that was particularly popular in the burgeoning green-ecological movement in the early 1970s.